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2023-08-24crash: move a few code bits to setup support of crash hotplugEric DeVolder3-218/+218
Patch series "crash: Kernel handling of CPU and memory hot un/plug", v28. Once the kdump service is loaded, if changes to CPUs or memory occur, either by hot un/plug or off/onlining, the crash elfcorehdr must also be updated. The elfcorehdr describes to kdump the CPUs and memory in the system, and any inaccuracies can result in a vmcore with missing CPU context or memory regions. The current solution utilizes udev to initiate an unload-then-reload of the kdump image (eg. kernel, initrd, boot_params, purgatory and elfcorehdr) by the userspace kexec utility. In the original post I outlined the significant performance problems related to offloading this activity to userspace. This patchset introduces a generic crash handler that registers with the CPU and memory notifiers. Upon CPU or memory changes, from either hot un/plug or off/onlining, this generic handler is invoked and performs important housekeeping, for example obtaining the appropriate lock, and then invokes an architecture specific handler to do the appropriate elfcorehdr update. Note the description in patch 'crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()' and 'x86/crash: optimize CPU changes' that enables further optimizations related to CPU plug/unplug/online/offline performance of elfcorehdr updates. In the case of x86_64, the arch specific handler generates a new elfcorehdr, and overwrites the old one in memory; thus no involvement with userspace needed. To realize the benefits/test this patchset, one must make a couple of minor changes to userspace: - Prevent udev from updating kdump crash kernel on hot un/plug changes. Add the following as the first lines to the RHEL udev rule file /usr/lib/udev/rules.d/98-kexec.rules: # The kernel updates the crash elfcorehdr for CPU and memory changes SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" With this changeset applied, the two rules evaluate to false for CPU and memory change events and thus skip the userspace unload-then-reload of kdump. - Change to the kexec_file_load for loading the kdump kernel: Eg. on RHEL: in /usr/bin/kdumpctl, change to: standard_kexec_args="-p -d -s" which adds the -s to select kexec_file_load() syscall. This kernel patchset also supports kexec_load() with a modified kexec userspace utility. A working changeset to the kexec userspace utility is posted to the kexec-tools mailing list here: http://lists.infradead.org/pipermail/kexec/2023-May/027049.html To use the kexec-tools patch, apply, build and install kexec-tools, then change the kdumpctl's standard_kexec_args to replace the -s with --hotplug. The removal of -s reverts to the kexec_load syscall and the addition of --hotplug invokes the changes put forth in the kexec-tools patch. This patch (of 8): The crash hotplug support leans on the work for the kexec_file_load() syscall. To also support the kexec_load() syscall, a few bits of code need to be move outside of CONFIG_KEXEC_FILE. As such, these bits are moved out of kexec_file.c and into a common location crash_core.c. In addition, struct crash_mem and crash_notes were moved to new locales so that PROC_KCORE, which sets CRASH_CORE alone, builds correctly. No functionality change intended. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Eric DeVolder <[email protected]> Reviewed-by: Sourabh Jain <[email protected]> Acked-by: Hari Bathini <[email protected]> Acked-by: Baoquan He <[email protected]> Cc: Akhil Raj <[email protected]> Cc: Bjorn Helgaas <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Dave Young <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Eric W. Biederman <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: Mimi Zohar <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Takashi Iwai <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Thomas Weißschuh <[email protected]> Cc: Valentin Schneider <[email protected]> Cc: Vivek Goyal <[email protected]> Cc: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-21treewide: drop CONFIG_EMBEDDEDRandy Dunlap1-1/+1
There is only one Kconfig user of CONFIG_EMBEDDED and it can be switched to EXPERT or "if !ARCH_MULTIPLATFORM" (suggested by Arnd). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Randy Dunlap <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]> Acked-by: Arnd Bergmann <[email protected]> Acked-by: Palmer Dabbelt <[email protected]> [RISC-V] Acked-by: Greg Ungerer <[email protected]> Acked-by: Jason A. Donenfeld <[email protected]> Acked-by: Michael Ellerman <[email protected]> [powerpc] Cc: Russell King <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Brian Cain <[email protected]> Cc: Michal Simek <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Dinh Nguyen <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: Stefan Kristiansson <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Albert Ou <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: John Paul Adrian Glaubitz <[email protected]> Cc: Max Filippov <[email protected]> Cc: Josh Triplett <[email protected]> Cc: Masahiro Yamada <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-21lockdep: fix static memory detection even moreHelge Deller1-22/+14
On the parisc architecture, lockdep reports for all static objects which are in the __initdata section (e.g. "setup_done" in devtmpfs, "kthreadd_done" in init/main.c) this warning: INFO: trying to register non-static key. The warning itself is wrong, because those objects are in the __initdata section, but the section itself is on parisc outside of range from _stext to _end, which is why the static_obj() functions returns a wrong answer. While fixing this issue, I noticed that the whole existing check can be simplified a lot. Instead of checking against the _stext and _end symbols (which include code areas too) just check for the .data and .bss segments (since we check a data object). This can be done with the existing is_kernel_core_data() macro. In addition objects in the __initdata section can be checked with init_section_contains(), and is_kernel_rodata() allows keys to be in the _ro_after_init section. This partly reverts and simplifies commit bac59d18c701 ("x86/setup: Fix static memory detection"). Link: https://lkml.kernel.org/r/ZNqrLRaOi/3wPAdp@p100 Fixes: bac59d18c701 ("x86/setup: Fix static memory detection") Signed-off-by: Helge Deller <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Guenter Roeck <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-21kernel/fork: stop playing lockless games for exe_file replacementMateusz Guzik1-13/+9
xchg originated in 6e399cd144d8 ("prctl: avoid using mmap_sem for exe_file serialization"). While the commit message does not explain *why* the change, I found the original submission [1] which ultimately claims it cleans things up by removing dependency of exe_file on the semaphore. However, fe69d560b5bd ("kernel/fork: always deny write access to current MM exe_file") added a semaphore up/down cycle to synchronize the state of exe_file against fork, defeating the point of the original change. This is on top of semaphore trips already present both in the replacing function and prctl (the only consumer). Normally replacing exe_file does not happen for busy processes, thus write-locking is not an impediment to performance in the intended use case. If someone keeps invoking the routine for a busy processes they are trying to play dirty and that's another reason to avoid any trickery. As such I think the atomic here only adds complexity for no benefit. Just write-lock around the replacement. I also note that replacement races against the mapping check loop as nothing synchronizes actual assignment with with said checks but I am not addressing it in this patch. (Is the loop of any use to begin with?) Link: https://lore.kernel.org/linux-mm/[email protected]/ [1] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Mateusz Guzik <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Acked-by: David Hildenbrand <[email protected]> Cc: "Christian Brauner (Microsoft)" <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: Eric W. Biederman <[email protected]> Cc: Konstantin Khlebnikov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mateusz Guzik <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18watchdog/hardlockup: avoid large stack frames in watchdog_hardlockup_check()Douglas Anderson1-7/+2
After commit 77c12fc95980 ("watchdog/hardlockup: add a "cpu" param to watchdog_hardlockup_check()") we started storing a `struct cpumask` on the stack in watchdog_hardlockup_check(). On systems with CONFIG_NR_CPUS set to 8192 this takes up 1K on the stack. That triggers warnings with `CONFIG_FRAME_WARN` set to 1024. We'll use the new trigger_allbutcpu_cpu_backtrace() to avoid needing to use a CPU mask at all. Link: https://lkml.kernel.org/r/20230804065935.v4.2.I501ab68cb926ee33a7c87e063d207abf09b9943c@changeid Fixes: 77c12fc95980 ("watchdog/hardlockup: add a "cpu" param to watchdog_hardlockup_check()") Signed-off-by: Douglas Anderson <[email protected]> Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/r/[email protected] Acked-by: Michal Hocko <[email protected]> Reviewed-by: Petr Mladek <[email protected]> Cc: Lecopzer Chen <[email protected]> Cc: Pingfan Liu <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18nmi_backtrace: allow excluding an arbitrary CPUDouglas Anderson1-1/+1
The APIs that allow backtracing across CPUs have always had a way to exclude the current CPU. This convenience means callers didn't need to find a place to allocate a CPU mask just to handle the common case. Let's extend the API to take a CPU ID to exclude instead of just a boolean. This isn't any more complex for the API to handle and allows the hardlockup detector to exclude a different CPU (the one it already did a trace for) without needing to find space for a CPU mask. Arguably, this new API also encourages safer behavior. Specifically if the caller wants to avoid tracing the current CPU (maybe because they already traced the current CPU) this makes it more obvious to the caller that they need to make sure that the current CPU ID can't change. [[email protected]: fix trigger_allbutcpu_cpu_backtrace() stub] Link: https://lkml.kernel.org/r/20230804065935.v4.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid Signed-off-by: Douglas Anderson <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: kernel test robot <[email protected]> Cc: Lecopzer Chen <[email protected]> Cc: Petr Mladek <[email protected]> Cc: Pingfan Liu <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18kthread: unexport __kthread_should_park()Greg Kroah-Hartman1-2/+1
There are no in-kernel users of __kthread_should_park() so mark it as static and do not export it. Link: https://lkml.kernel.org/r/2023080450-handcuff-stump-1d6e@gregkh Signed-off-by: Greg Kroah-Hartman <[email protected]> Reviewed-by: Kees Cook <[email protected]> Cc: John Stultz <[email protected]> Cc: "Peter Zijlstra (Intel)" <[email protected]> Cc: "Arve Hjønnevåg" <[email protected]> Cc: Valentin Schneider <[email protected]> Cc: Andrew Morton <[email protected]> Cc: "Christian Brauner (Microsoft)" <[email protected]> Cc: Mike Christie <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Zqiang <[email protected]> Cc: Prathu Baronia <[email protected]> Cc: Sami Tolvanen <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18gcov: shut up missing prototype warnings for internal stubsArnd Bergmann1-0/+2
gcov uses global functions that are called from generated code, but these have no prototype in a header, which causes a W=1 build warning: kernel/gcov/gcc_base.c:12:6: error: no previous prototype for '__gcov_init' [-Werror=missing-prototypes] kernel/gcov/gcc_base.c:40:6: error: no previous prototype for '__gcov_flush' [-Werror=missing-prototypes] kernel/gcov/gcc_base.c:46:6: error: no previous prototype for '__gcov_merge_add' [-Werror=missing-prototypes] kernel/gcov/gcc_base.c:52:6: error: no previous prototype for '__gcov_merge_single' [-Werror=missing-prototypes] Just turn off these warnings unconditionally for the two files that contain them. Link: https://lore.kernel.org/all/[email protected]/ Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Arnd Bergmann <[email protected]> Tested-by: Peter Oberparleiter <[email protected]> Acked-by: Peter Oberparleiter <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18kernel: relay: remove unnecessary NULL values from relay_open_bufLi kunyu1-1/+1
buf is assigned first, so it does not need to initialize the assignment. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Li kunyu <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18remove ARCH_DEFAULT_KEXEC from Kconfig.kexecEric DeVolder1-1/+0
This patch is a minor cleanup to the series "refactor Kconfig to consolidate KEXEC and CRASH options". In that series, a new option ARCH_DEFAULT_KEXEC was introduced in order to obtain the equivalent behavior of s390 original Kconfig settings for KEXEC. As it turns out, this new option did not fully provide the equivalent behavior, rather a "select KEXEC" did. As such, the ARCH_DEFAULT_KEXEC is not needed anymore, so remove it. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Eric DeVolder <[email protected]> Acked-by: Alexander Gordeev <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18kexec: rename ARCH_HAS_KEXEC_PURGATORYEric DeVolder1-3/+3
The Kconfig refactor to consolidate KEXEC and CRASH options utilized option names of the form ARCH_SUPPORTS_<option>. Thus rename the ARCH_HAS_KEXEC_PURGATORY to ARCH_SUPPORTS_KEXEC_PURGATORY to follow the same. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Eric DeVolder <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18kexec: consolidate kexec and crash options into kernel/Kconfig.kexecEric DeVolder1-0/+116
Patch series "refactor Kconfig to consolidate KEXEC and CRASH options", v6. The Kconfig is refactored to consolidate KEXEC and CRASH options from various arch/<arch>/Kconfig files into new file kernel/Kconfig.kexec. The Kconfig.kexec is now a submenu titled "Kexec and crash features" located under "General Setup". The following options are impacted: - KEXEC - KEXEC_FILE - KEXEC_SIG - KEXEC_SIG_FORCE - KEXEC_IMAGE_VERIFY_SIG - KEXEC_BZIMAGE_VERIFY_SIG - KEXEC_JUMP - CRASH_DUMP Over time, these options have been copied between Kconfig files and are very similar to one another, but with slight differences. The following architectures are impacted by the refactor (because of use of one or more KEXEC/CRASH options): - arm - arm64 - ia64 - loongarch - m68k - mips - parisc - powerpc - riscv - s390 - sh - x86 More information: In the patch series "crash: Kernel handling of CPU and memory hot un/plug" https://lore.kernel.org/lkml/[email protected]/ the new kernel feature introduces the config option CRASH_HOTPLUG. In reviewing, Thomas Gleixner requested that the new config option not be placed in x86 Kconfig. Rather the option needs a generic/common home. To Thomas' point, the KEXEC and CRASH options have largely been duplicated in the various arch/<arch>/Kconfig files, with minor differences. This kind of proliferation is to be avoid/stopped. https://lore.kernel.org/lkml/875y91yv63.ffs@tglx/ To that end, I have refactored the arch Kconfigs so as to consolidate the various KEXEC and CRASH options. Generally speaking, this work has the following themes: - KEXEC and CRASH options are moved into new file kernel/Kconfig.kexec - These items from arch/Kconfig: CRASH_CORE KEXEC_CORE KEXEC_ELF HAVE_IMA_KEXEC - These items from arch/x86/Kconfig form the common options: KEXEC KEXEC_FILE KEXEC_SIG KEXEC_SIG_FORCE KEXEC_BZIMAGE_VERIFY_SIG KEXEC_JUMP CRASH_DUMP - These items from arch/arm64/Kconfig form the common options: KEXEC_IMAGE_VERIFY_SIG - The crash hotplug series appends CRASH_HOTPLUG to Kconfig.kexec - The Kconfig.kexec is now a submenu titled "Kexec and crash features" and is now listed in "General Setup" submenu from init/Kconfig. - To control the common options, each has a new ARCH_SUPPORTS_<option> option. These gateway options determine whether the common options options are valid for the architecture. - To account for the slight differences in the original architecture coding of the common options, each now has a corresponding ARCH_SELECTS_<option> which are used to elicit the same side effects as the original arch/<arch>/Kconfig files for KEXEC and CRASH options. An example, 'make menuconfig' illustrating the submenu: > General setup > Kexec and crash features [*] Enable kexec system call [*] Enable kexec file based system call [*] Verify kernel signature during kexec_file_load() syscall [ ] Require a valid signature in kexec_file_load() syscall [ ] Enable bzImage signature verification support [*] kexec jump [*] kernel crash dumps [*] Update the crash elfcorehdr on system configuration changes In the process of consolidating the common options, I encountered slight differences in the coding of these options in several of the architectures. As a result, I settled on the following solution: - Each of the common options has a 'depends on ARCH_SUPPORTS_<option>' statement. For example, the KEXEC_FILE option has a 'depends on ARCH_SUPPORTS_KEXEC_FILE' statement. This approach is needed on all common options so as to prevent options from appearing for architectures which previously did not allow/enable them. For example, arm supports KEXEC but not KEXEC_FILE. The arch/arm/Kconfig does not provide ARCH_SUPPORTS_KEXEC_FILE and so KEXEC_FILE and related options are not available to arm. - The boolean ARCH_SUPPORTS_<option> in effect allows the arch to determine when the feature is allowed. Archs which don't have the feature simply do not provide the corresponding ARCH_SUPPORTS_<option>. For each arch, where there previously were KEXEC and/or CRASH options, these have been replaced with the corresponding boolean ARCH_SUPPORTS_<option>, and an appropriate def_bool statement. For example, if the arch supports KEXEC_FILE, then the ARCH_SUPPORTS_KEXEC_FILE simply has a 'def_bool y'. This permits the KEXEC_FILE option to be available. If the arch has a 'depends on' statement in its original coding of the option, then that expression becomes part of the def_bool expression. For example, arm64 had: config KEXEC depends on PM_SLEEP_SMP and in this solution, this converts to: config ARCH_SUPPORTS_KEXEC def_bool PM_SLEEP_SMP - In order to account for the architecture differences in the coding for the common options, the ARCH_SELECTS_<option> in the arch/<arch>/Kconfig is used. This option has a 'depends on <option>' statement to couple it to the main option, and from there can insert the differences from the common option and the arch original coding of that option. For example, a few archs enable CRYPTO and CRYTPO_SHA256 for KEXEC_FILE. These require a ARCH_SELECTS_KEXEC_FILE and 'select CRYPTO' and 'select CRYPTO_SHA256' statements. Illustrating the option relationships: For each of the common KEXEC and CRASH options: ARCH_SUPPORTS_<option> <- <option> <- ARCH_SELECTS_<option> <option> # in Kconfig.kexec ARCH_SUPPORTS_<option> # in arch/<arch>/Kconfig, as needed ARCH_SELECTS_<option> # in arch/<arch>/Kconfig, as needed For example, KEXEC: ARCH_SUPPORTS_KEXEC <- KEXEC <- ARCH_SELECTS_KEXEC KEXEC # in Kconfig.kexec ARCH_SUPPORTS_KEXEC # in arch/<arch>/Kconfig, as needed ARCH_SELECTS_KEXEC # in arch/<arch>/Kconfig, as needed To summarize, the ARCH_SUPPORTS_<option> permits the <option> to be enabled, and the ARCH_SELECTS_<option> handles side effects (ie. select statements). Examples: A few examples to show the new strategy in action: ===== x86 (minus the help section) ===== Original: config KEXEC bool "kexec system call" select KEXEC_CORE config KEXEC_FILE bool "kexec file based system call" select KEXEC_CORE select HAVE_IMA_KEXEC if IMA depends on X86_64 depends on CRYPTO=y depends on CRYPTO_SHA256=y config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE config KEXEC_SIG bool "Verify kernel signature during kexec_file_load() syscall" depends on KEXEC_FILE config KEXEC_SIG_FORCE bool "Require a valid signature in kexec_file_load() syscall" depends on KEXEC_SIG config KEXEC_BZIMAGE_VERIFY_SIG bool "Enable bzImage signature verification support" depends on KEXEC_SIG depends on SIGNED_PE_FILE_VERIFICATION select SYSTEM_TRUSTED_KEYRING config CRASH_DUMP bool "kernel crash dumps" depends on X86_64 || (X86_32 && HIGHMEM) config KEXEC_JUMP bool "kexec jump" depends on KEXEC && HIBERNATION help becomes... New: config ARCH_SUPPORTS_KEXEC def_bool y config ARCH_SUPPORTS_KEXEC_FILE def_bool X86_64 && CRYPTO && CRYPTO_SHA256 config ARCH_SELECTS_KEXEC_FILE def_bool y depends on KEXEC_FILE select HAVE_IMA_KEXEC if IMA config ARCH_SUPPORTS_KEXEC_PURGATORY def_bool KEXEC_FILE config ARCH_SUPPORTS_KEXEC_SIG def_bool y config ARCH_SUPPORTS_KEXEC_SIG_FORCE def_bool y config ARCH_SUPPORTS_KEXEC_BZIMAGE_VERIFY_SIG def_bool y config ARCH_SUPPORTS_KEXEC_JUMP def_bool y config ARCH_SUPPORTS_CRASH_DUMP def_bool X86_64 || (X86_32 && HIGHMEM) ===== powerpc (minus the help section) ===== Original: config KEXEC bool "kexec system call" depends on PPC_BOOK3S || PPC_E500 || (44x && !SMP) select KEXEC_CORE config KEXEC_FILE bool "kexec file based system call" select KEXEC_CORE select HAVE_IMA_KEXEC if IMA select KEXEC_ELF depends on PPC64 depends on CRYPTO=y depends on CRYPTO_SHA256=y config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE config CRASH_DUMP bool "Build a dump capture kernel" depends on PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x && !SMP) select RELOCATABLE if PPC64 || 44x || PPC_85xx becomes... New: config ARCH_SUPPORTS_KEXEC def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP) config ARCH_SUPPORTS_KEXEC_FILE def_bool PPC64 && CRYPTO=y && CRYPTO_SHA256=y config ARCH_SUPPORTS_KEXEC_PURGATORY def_bool KEXEC_FILE config ARCH_SELECTS_KEXEC_FILE def_bool y depends on KEXEC_FILE select KEXEC_ELF select HAVE_IMA_KEXEC if IMA config ARCH_SUPPORTS_CRASH_DUMP def_bool PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x && !SMP) config ARCH_SELECTS_CRASH_DUMP def_bool y depends on CRASH_DUMP select RELOCATABLE if PPC64 || 44x || PPC_85xx Testing Approach and Results There are 388 config files in the arch/<arch>/configs directories. For each of these config files, a .config is generated both before and after this Kconfig series, and checked for equivalence. This approach allows for a rather rapid check of all architectures and a wide variety of configs wrt/ KEXEC and CRASH, and avoids requiring compiling for all architectures and running kernels and run-time testing. For each config file, the olddefconfig, allnoconfig and allyesconfig targets are utilized. In testing the randconfig has revealed problems as well, but is not used in the before and after equivalence check since one can not generate the "same" .config for before and after, even if using the same KCONFIG_SEED since the option list is different. As such, the following script steps compare the before and after of 'make olddefconfig'. The new symbols introduced by this series are filtered out, but otherwise the config files are PASS only if they were equivalent, and FAIL otherwise. The script performs the test by doing the following: # Obtain the "golden" .config output for given config file # Reset test sandbox git checkout master git branch -D test_Kconfig git checkout -B test_Kconfig master make distclean # Write out updated config cp -f <config file> .config make ARCH=<arch> olddefconfig # Track each item in .config, LHSB is "golden" scoreboard .config # Obtain the "changed" .config output for given config file # Reset test sandbox make distclean # Apply this Kconfig series git am <this Kconfig series> # Write out updated config cp -f <config file> .config make ARCH=<arch> olddefconfig # Track each item in .config, RHSB is "changed" scoreboard .config # Determine test result # Filter-out new symbols introduced by this series # Filter-out symbol=n which not in either scoreboard # Compare LHSB "golden" and RHSB "changed" scoreboards and issue PASS/FAIL The script was instrumental during the refactoring of Kconfig as it continually revealed problems. The end result being that the solution presented in this series passes all configs as checked by the script, with the following exceptions: - arch/ia64/configs/zx1_config with olddefconfig This config file has: # CONFIG_KEXEC is not set CONFIG_CRASH_DUMP=y and this refactor now couples KEXEC to CRASH_DUMP, so it is not possible to enable CRASH_DUMP without KEXEC. - arch/sh/configs/* with allyesconfig The arch/sh/Kconfig codes CRASH_DUMP as dependent upon BROKEN_ON_MMU (which clearly is not meant to be set). This symbol is not provided but with the allyesconfig it is set to yes which enables CRASH_DUMP. But KEXEC is coded as dependent upon MMU, and is set to no in arch/sh/mm/Kconfig, so KEXEC is not enabled. This refactor now couples KEXEC to CRASH_DUMP, so it is not possible to enable CRASH_DUMP without KEXEC. While the above exceptions are not equivalent to their original, the config file produced is valid (and in fact better wrt/ CRASH_DUMP handling). This patch (of 14) The config options for kexec and crash features are consolidated into new file kernel/Kconfig.kexec. Under the "General Setup" submenu is a new submenu "Kexec and crash handling". All the kexec and crash options that were once in the arch-dependent submenu "Processor type and features" are now consolidated in the new submenu. The following options are impacted: - KEXEC - KEXEC_FILE - KEXEC_SIG - KEXEC_SIG_FORCE - KEXEC_BZIMAGE_VERIFY_SIG - KEXEC_JUMP - CRASH_DUMP The three main options are KEXEC, KEXEC_FILE and CRASH_DUMP. Architectures specify support of certain KEXEC and CRASH features with similarly named new ARCH_SUPPORTS_<option> config options. Architectures can utilize the new ARCH_SELECTS_<option> config options to specify additional components when <option> is enabled. To summarize, the ARCH_SUPPORTS_<option> permits the <option> to be enabled, and the ARCH_SELECTS_<option> handles side effects (ie. select statements). Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Eric DeVolder <[email protected]> Cc: Albert Ou <[email protected]> Cc: Alexander Gordeev <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Baoquan He <[email protected]> Cc: Borislav Petkov (AMD) <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Cc. "H. Peter Anvin" <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Dave Hansen <[email protected]> # for x86 Cc: Frederic Weisbecker <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Hari Bathini <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: John Paul Adrian Glaubitz <[email protected]> Cc: Juerg Haefliger <[email protected]> Cc: Kees Cook <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Marc Aurèle La France <[email protected]> Cc: Masahiro Yamada <[email protected]> Cc: Masami Hiramatsu (Google) <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Miguel Ojeda <[email protected]> Cc: Mike Rapoport (IBM) <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Russell King (Oracle) <[email protected]> Cc: Sami Tolvanen <[email protected]> Cc: Sebastian Reichel <[email protected]> Cc: Sourabh Jain <[email protected]> Cc: Sven Schnelle <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: WANG Xuerui <[email protected]> Cc: Will Deacon <[email protected]> Cc: Xin Li <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Zhen Lei <[email protected]> Cc: Zi Yan <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18acct: replace all non-returning strlcpy with strscpyAzeem Shaikh1-1/+1
strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). No return values were used, so direct replacement is safe. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Azeem Shaikh <[email protected]> Cc: Kees Cook <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18signal: print comm and exe name on fatal signalsVincent Whitchurch1-1/+12
Make the print-fatal-signals message more useful by printing the comm and the exe name for the process which received the fatal signal: Before: potentially unexpected fatal signal 4 potentially unexpected fatal signal 11 After: buggy-program: pool: potentially unexpected fatal signal 4 some-daemon: gdbus: potentially unexpected fatal signal 11 comm used to be present but was removed in commit 681a90ffe829b8ee25d ("arc, print-fatal-signals: reduce duplicated information") because it's also included as part of the later stack trace. Having the comm as part of the main "unexpected fatal..." print is rather useful though when analysing logs, and the exe name is also valuable as shown in the examples above where the comm ends up having some generic name like "pool". [[email protected]: don't include linux/file.h twice] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Vincent Whitchurch <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Vineet Gupta <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-08-18cred: convert printks to pr_<level>tiozhang1-12/+15
Use current logging style. Link: https://lkml.kernel.org/r/20230625033452.GA22858@didi-ThinkCentre-M930t-N000 Signed-off-by: tiozhang <[email protected]> Reviewed-by: Sergey Senozhatsky <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Joe Perches <[email protected]> Cc: Kees Cook <[email protected]> Cc: Luis Chamberlain <[email protected]> Cc: Paulo Alcantara <[email protected]> Cc: Weiping Zhang <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-07-30Merge tag 'probes-fixes-v6.5-rc3' of ↵Linus Torvalds2-5/+17
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probe fixes from Masami Hiramatsu: - probe-events: add NULL check for some BTF API calls which can return error code and NULL. - ftrace selftests: check fprobe and kprobe event correctly. This fixes a miss condition of the test command. - kprobes: do not allow probing functions that start with "__cfi_" or "__pfx_" since those are auto generated for kernel CFI and not executed. * tag 'probes-fixes-v6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: kprobes: Prohibit probing on CFI preamble symbol selftests/ftrace: Fix to check fprobe event eneblement tracing/probes: Fix to add NULL check for BTF APIs
2023-07-30Merge tag 'locking_urgent_for_v6.5_rc4' of ↵Linus Torvalds4-76/+155
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Borislav Petkov: - Fix a rtmutex race condition resulting from sharing of the sort key between the lock waiters and the PI chain tree (->pi_waiters) of a task by giving each tree their own sort key * tag 'locking_urgent_for_v6.5_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rtmutex: Fix task->pi_waiters integrity
2023-07-29Merge tag 'trace-v6.5-rc3' of ↵Linus Torvalds5-22/+21
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix to /sys/kernel/tracing/per_cpu/cpu*/stats read and entries. If a resize shrinks the buffer it clears the read count to notify readers that they need to reset. But the read count is also used for accounting and this causes the numbers to be off. Instead, create a separate variable to use to notify readers to reset. - Fix the ref counts of the "soft disable" mode. The wrong value was used for testing if soft disable mode should be enabled or disable, but instead, just change the logic to do the enable and disable in place when the SOFT_MODE is set or cleared. - Several kernel-doc fixes - Removal of unused external declarations * tag 'trace-v6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix warning in trace_buffered_event_disable() ftrace: Remove unused extern declarations tracing: Fix kernel-doc warnings in trace_seq.c tracing: Fix kernel-doc warnings in trace_events_trigger.c tracing/synthetic: Fix kernel-doc warnings in trace_events_synth.c ring-buffer: Fix kernel-doc warnings in ring_buffer.c ring-buffer: Fix wrong stat of cpu_buffer->read
2023-07-29kprobes: Prohibit probing on CFI preamble symbolMasami Hiramatsu (Google)1-1/+13
Do not allow to probe on "__cfi_" or "__pfx_" started symbol, because those are used for CFI and not executed. Probing it will break the CFI. Link: https://lore.kernel.org/all/168904024679.116016.18089228029322008512.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-28tracing: Fix warning in trace_buffered_event_disable()Zheng Yejian1-10/+4
Warning happened in trace_buffered_event_disable() at WARN_ON_ONCE(!trace_buffered_event_ref) Call Trace: ? __warn+0xa5/0x1b0 ? trace_buffered_event_disable+0x189/0x1b0 __ftrace_event_enable_disable+0x19e/0x3e0 free_probe_data+0x3b/0xa0 unregister_ftrace_function_probe_func+0x6b8/0x800 event_enable_func+0x2f0/0x3d0 ftrace_process_regex.isra.0+0x12d/0x1b0 ftrace_filter_write+0xe6/0x140 vfs_write+0x1c9/0x6f0 [...] The cause of the warning is in __ftrace_event_enable_disable(), trace_buffered_event_enable() was called once while trace_buffered_event_disable() was called twice. Reproduction script show as below, for analysis, see the comments: ``` #!/bin/bash cd /sys/kernel/tracing/ # 1. Register a 'disable_event' command, then: # 1) SOFT_DISABLED_BIT was set; # 2) trace_buffered_event_enable() was called first time; echo 'cmdline_proc_show:disable_event:initcall:initcall_finish' > \ set_ftrace_filter # 2. Enable the event registered, then: # 1) SOFT_DISABLED_BIT was cleared; # 2) trace_buffered_event_disable() was called first time; echo 1 > events/initcall/initcall_finish/enable # 3. Try to call into cmdline_proc_show(), then SOFT_DISABLED_BIT was # set again!!! cat /proc/cmdline # 4. Unregister the 'disable_event' command, then: # 1) SOFT_DISABLED_BIT was cleared again; # 2) trace_buffered_event_disable() was called second time!!! echo '!cmdline_proc_show:disable_event:initcall:initcall_finish' > \ set_ftrace_filter ``` To fix it, IIUC, we can change to call trace_buffered_event_enable() at fist time soft-mode enabled, and call trace_buffered_event_disable() at last time soft-mode disabled. Link: https://lore.kernel.org/linux-trace-kernel/[email protected] Cc: <[email protected]> Fixes: 0fc1b09ff1ff ("tracing: Use temp buffer when filtering events") Signed-off-by: Zheng Yejian <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-28tracing: Fix kernel-doc warnings in trace_seq.cGaosheng Cui1-0/+1
Fix kernel-doc warning: kernel/trace/trace_seq.c:142: warning: Function parameter or member 'args' not described in 'trace_seq_vprintf' Link: https://lkml.kernel.org/r/[email protected] Cc: <[email protected]> Signed-off-by: Gaosheng Cui <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-28tracing: Fix kernel-doc warnings in trace_events_trigger.cGaosheng Cui1-0/+2
Fix kernel-doc warnings: kernel/trace/trace_events_trigger.c:59: warning: Function parameter or member 'buffer' not described in 'event_triggers_call' kernel/trace/trace_events_trigger.c:59: warning: Function parameter or member 'event' not described in 'event_triggers_call' Link: https://lkml.kernel.org/r/[email protected] Cc: <[email protected]> Signed-off-by: Gaosheng Cui <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-28tracing/synthetic: Fix kernel-doc warnings in trace_events_synth.cGaosheng Cui1-0/+1
Fix kernel-doc warning: kernel/trace/trace_events_synth.c:1257: warning: Function parameter or member 'mod' not described in 'synth_event_gen_cmd_array_start' Link: https://lkml.kernel.org/r/[email protected] Cc: <[email protected]> Signed-off-by: Gaosheng Cui <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-28ring-buffer: Fix kernel-doc warnings in ring_buffer.cGaosheng Cui1-2/+1
Fix kernel-doc warnings: kernel/trace/ring_buffer.c:954: warning: Function parameter or member 'cpu' not described in 'ring_buffer_wake_waiters' kernel/trace/ring_buffer.c:3383: warning: Excess function parameter 'event' description in 'ring_buffer_unlock_commit' kernel/trace/ring_buffer.c:5359: warning: Excess function parameter 'cpu' description in 'ring_buffer_reset_online_cpus' Link: https://lkml.kernel.org/r/[email protected] Cc: <[email protected]> Signed-off-by: Gaosheng Cui <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-28ring-buffer: Fix wrong stat of cpu_buffer->readZheng Yejian1-10/+12
When pages are removed in rb_remove_pages(), 'cpu_buffer->read' is set to 0 in order to make sure any read iterators reset themselves. However, this will mess 'entries' stating, see following steps: # cd /sys/kernel/tracing/ # 1. Enlarge ring buffer prepare for later reducing: # echo 20 > per_cpu/cpu0/buffer_size_kb # 2. Write a log into ring buffer of cpu0: # taskset -c 0 echo "hello1" > trace_marker # 3. Read the log: # cat per_cpu/cpu0/trace_pipe <...>-332 [000] ..... 62.406844: tracing_mark_write: hello1 # 4. Stop reading and see the stats, now 0 entries, and 1 event readed: # cat per_cpu/cpu0/stats entries: 0 [...] read events: 1 # 5. Reduce the ring buffer # echo 7 > per_cpu/cpu0/buffer_size_kb # 6. Now entries became unexpected 1 because actually no entries!!! # cat per_cpu/cpu0/stats entries: 1 [...] read events: 0 To fix it, introduce 'page_removed' field to count total removed pages since last reset, then use it to let read iterators reset themselves instead of changing the 'read' pointer. Link: https://lore.kernel.org/linux-trace-kernel/[email protected] Cc: <[email protected]> Cc: <[email protected]> Fixes: 83f40318dab0 ("ring-buffer: Make removal of ring buffer pages atomic") Signed-off-by: Zheng Yejian <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-26mm: suppress mm fault logging if fatal signal already pendingLinus Torvalds1-0/+4
Commit eda0047296a1 ("mm: make the page fault mmap locking killable") intentionally made it much easier to trigger the "page fault fails because a fatal signal is pending" situation, by having the mmap locking fail early in that case. We have long aborted page faults in other fatal cases when the actual IO for a page is interrupted by SIGKILL - which is particularly useful for the traditional case of NFS hanging due to network issues, but local filesystems could cause it too if you happened to get the SIGKILL while waiting for a page to be faulted in (eg lock_folio_maybe_drop_mmap()). So aborting the page fault wasn't a new condition - but it now triggers earlier, before we even get to 'handle_mm_fault()'. And as a result the error doesn't go through our 'fault_signal_pending()' logic, and doesn't get filtered away there. Normally you'd never even notice, because if a fatal signal is pending, the new SIGSEGV we send ends up being ignored anyway. But it turns out that there is one very noticeable exception: if you enable 'show_unhandled_signals', the aborted page fault will be logged in the kernel messages, and you'll get a scary line looking something like this in your logs: pverados[2183248]: segfault at 55e5a00f9ae0 ip 000055e5a00f9ae0 sp 00007ffc0720bea8 error 14 in perl[55e5a00d4000+195000] likely on CPU 10 (core 4, socket 0) which is rather misleading. It's not really a segfault at all, it's just "the thread was killed before the page fault completed, so we aborted the page fault". Fix this by just making it clear that a pending fatal signal means that any new signal coming in after that is implicitly handled. This will avoid the misleading logging, since now the signal isn't 'unhandled' any more. Reported-and-tested-by: Fiona Ebner <[email protected]> Tested-by: Thomas Lamprecht <[email protected]> Link: https://lore.kernel.org/lkml/[email protected]/ Acked-by: Oleg Nesterov <[email protected]> Fixes: eda0047296a1 ("mm: make the page fault mmap locking killable") Signed-off-by: Linus Torvalds <[email protected]>
2023-07-26tracing/probes: Fix to add NULL check for BTF APIsMasami Hiramatsu (Google)1-4/+4
Since find_btf_func_param() abd btf_type_by_id() can return NULL, the caller must check the return value correctly. Link: https://lore.kernel.org/all/169024903951.395371.11361556840733470934.stgit@devnote2/ Fixes: b576e09701c7 ("tracing/probes: Support function parameters if BTF is available") Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-23Merge tag 'trace-v6.5-rc2' of ↵Linus Torvalds4-7/+17
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Swapping the ring buffer for snapshotting (for things like irqsoff) can crash if the ring buffer is being resized. Disable swapping when this happens. The missed swap will be reported to the tracer - Report error if the histogram fails to be created due to an error in adding a histogram variable, in event_hist_trigger_parse() - Remove unused declaration of tracing_map_set_field_descr() * tag 'trace-v6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/histograms: Return an error if we fail to add histogram to hist_vars list ring-buffer: Do not swap cpu_buffer during resize process tracing: Remove unused extern declaration tracing_map_set_field_descr()
2023-07-23tracing/histograms: Return an error if we fail to add histogram to hist_vars ↵Mohamed Khalfella1-1/+2
list Commit 6018b585e8c6 ("tracing/histograms: Add histograms to hist_vars if they have referenced variables") added a check to fail histogram creation if save_hist_vars() failed to add histogram to hist_vars list. But the commit failed to set ret to failed return code before jumping to unregister histogram, fix it. Link: https://lore.kernel.org/linux-trace-kernel/[email protected] Cc: [email protected] Fixes: 6018b585e8c6 ("tracing/histograms: Add histograms to hist_vars if they have referenced variables") Signed-off-by: Mohamed Khalfella <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-23ring-buffer: Do not swap cpu_buffer during resize processChen Lin2-2/+15
When ring_buffer_swap_cpu was called during resize process, the cpu buffer was swapped in the middle, resulting in incorrect state. Continuing to run in the wrong state will result in oops. This issue can be easily reproduced using the following two scripts: /tmp # cat test1.sh //#! /bin/sh for i in `seq 0 100000` do echo 2000 > /sys/kernel/debug/tracing/buffer_size_kb sleep 0.5 echo 5000 > /sys/kernel/debug/tracing/buffer_size_kb sleep 0.5 done /tmp # cat test2.sh //#! /bin/sh for i in `seq 0 100000` do echo irqsoff > /sys/kernel/debug/tracing/current_tracer sleep 1 echo nop > /sys/kernel/debug/tracing/current_tracer sleep 1 done /tmp # ./test1.sh & /tmp # ./test2.sh & A typical oops log is as follows, sometimes with other different oops logs. [ 231.711293] WARNING: CPU: 0 PID: 9 at kernel/trace/ring_buffer.c:2026 rb_update_pages+0x378/0x3f8 [ 231.713375] Modules linked in: [ 231.714735] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G W 6.5.0-rc1-00276-g20edcec23f92 #15 [ 231.716750] Hardware name: linux,dummy-virt (DT) [ 231.718152] Workqueue: events update_pages_handler [ 231.719714] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 231.721171] pc : rb_update_pages+0x378/0x3f8 [ 231.722212] lr : rb_update_pages+0x25c/0x3f8 [ 231.723248] sp : ffff800082b9bd50 [ 231.724169] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000 [ 231.726102] x26: 0000000000000001 x25: fffffffffffff010 x24: 0000000000000ff0 [ 231.728122] x23: ffff0000c3a0b600 x22: ffff0000c3a0b5c0 x21: fffffffffffffe0a [ 231.730203] x20: ffff0000c3a0b600 x19: ffff0000c0102400 x18: 0000000000000000 [ 231.732329] x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffe7aa8510 [ 231.734212] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000002 [ 231.736291] x11: ffff8000826998a8 x10: ffff800082b9baf0 x9 : ffff800081137558 [ 231.738195] x8 : fffffc00030e82c8 x7 : 0000000000000000 x6 : 0000000000000001 [ 231.740192] x5 : ffff0000ffbafe00 x4 : 0000000000000000 x3 : 0000000000000000 [ 231.742118] x2 : 00000000000006aa x1 : 0000000000000001 x0 : ffff0000c0007208 [ 231.744196] Call trace: [ 231.744892] rb_update_pages+0x378/0x3f8 [ 231.745893] update_pages_handler+0x1c/0x38 [ 231.746893] process_one_work+0x1f0/0x468 [ 231.747852] worker_thread+0x54/0x410 [ 231.748737] kthread+0x124/0x138 [ 231.749549] ret_from_fork+0x10/0x20 [ 231.750434] ---[ end trace 0000000000000000 ]--- [ 233.720486] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 233.721696] Mem abort info: [ 233.721935] ESR = 0x0000000096000004 [ 233.722283] EC = 0x25: DABT (current EL), IL = 32 bits [ 233.722596] SET = 0, FnV = 0 [ 233.722805] EA = 0, S1PTW = 0 [ 233.723026] FSC = 0x04: level 0 translation fault [ 233.723458] Data abort info: [ 233.723734] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 233.724176] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 233.724589] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 233.725075] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000104943000 [ 233.725592] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ 233.726231] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 233.726720] Modules linked in: [ 233.727007] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G W 6.5.0-rc1-00276-g20edcec23f92 #15 [ 233.727777] Hardware name: linux,dummy-virt (DT) [ 233.728225] Workqueue: events update_pages_handler [ 233.728655] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 233.729054] pc : rb_update_pages+0x1a8/0x3f8 [ 233.729334] lr : rb_update_pages+0x154/0x3f8 [ 233.729592] sp : ffff800082b9bd50 [ 233.729792] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000 [ 233.730220] x26: 0000000000000000 x25: ffff800082a8b840 x24: ffff0000c0102418 [ 233.730653] x23: 0000000000000000 x22: fffffc000304c880 x21: 0000000000000003 [ 233.731105] x20: 00000000000001f4 x19: ffff0000c0102400 x18: ffff800082fcbc58 [ 233.731727] x17: 0000000000000000 x16: 0000000000000001 x15: 0000000000000001 [ 233.732282] x14: ffff8000825fe0c8 x13: 0000000000000001 x12: 0000000000000000 [ 233.732709] x11: ffff8000826998a8 x10: 0000000000000ae0 x9 : ffff8000801b760c [ 233.733148] x8 : fefefefefefefeff x7 : 0000000000000018 x6 : ffff0000c03298c0 [ 233.733553] x5 : 0000000000000002 x4 : 0000000000000000 x3 : 0000000000000000 [ 233.733972] x2 : ffff0000c3a0b600 x1 : 0000000000000000 x0 : 0000000000000000 [ 233.734418] Call trace: [ 233.734593] rb_update_pages+0x1a8/0x3f8 [ 233.734853] update_pages_handler+0x1c/0x38 [ 233.735148] process_one_work+0x1f0/0x468 [ 233.735525] worker_thread+0x54/0x410 [ 233.735852] kthread+0x124/0x138 [ 233.736064] ret_from_fork+0x10/0x20 [ 233.736387] Code: 92400000 910006b5 aa000021 aa0303f7 (f9400060) [ 233.736959] ---[ end trace 0000000000000000 ]--- After analysis, the seq of the error is as follows [1-5]: int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size, int cpu_id) { for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; //1. get cpu_buffer, aka cpu_buffer(A) ... ... schedule_work_on(cpu, &cpu_buffer->update_pages_work); //2. 'update_pages_work' is queue on 'cpu', cpu_buffer(A) is passed to // update_pages_handler, do the update process, set 'update_done' in // complete(&cpu_buffer->update_done) and to wakeup resize process. //----> //3. Just at this moment, ring_buffer_swap_cpu is triggered, //cpu_buffer(A) be swaped to cpu_buffer(B), the max_buffer. //ring_buffer_swap_cpu is called as the 'Call trace' below. Call trace: dump_backtrace+0x0/0x2f8 show_stack+0x18/0x28 dump_stack+0x12c/0x188 ring_buffer_swap_cpu+0x2f8/0x328 update_max_tr_single+0x180/0x210 check_critical_timing+0x2b4/0x2c8 tracer_hardirqs_on+0x1c0/0x200 trace_hardirqs_on+0xec/0x378 el0_svc_common+0x64/0x260 do_el0_svc+0x90/0xf8 el0_svc+0x20/0x30 el0_sync_handler+0xb0/0xb8 el0_sync+0x180/0x1c0 //<---- /* wait for all the updates to complete */ for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; //4. get cpu_buffer, cpu_buffer(B) is used in the following process, //the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong. //for example, cpu_buffer(A)->update_done will leave be set 1, and will //not 'wait_for_completion' at the next resize round. if (!cpu_buffer->nr_pages_to_update) continue; if (cpu_online(cpu)) wait_for_completion(&cpu_buffer->update_done); cpu_buffer->nr_pages_to_update = 0; } ... } //5. the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong, //Continuing to run in the wrong state, then oops occurs. Link: https://lore.kernel.org/linux-trace-kernel/[email protected] Signed-off-by: Chen Lin <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-23tracing: Remove unused extern declaration tracing_map_set_field_descr()YueHaibing1-4/+0
Since commit 08d43a5fa063 ("tracing: Add lock-free tracing_map"), this is never used, so can be removed. Link: https://lore.kernel.org/linux-trace-kernel/[email protected] Cc: <[email protected]> Signed-off-by: YueHaibing <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-07-20Merge tag 'net-6.5-rc3' of ↵Linus Torvalds1-7/+25
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from BPF, netfilter, bluetooth and CAN. Current release - regressions: - eth: r8169: multiple fixes for PCIe ASPM-related problems - vrf: fix RCU lockdep splat in output path Previous releases - regressions: - gso: fall back to SW segmenting with GSO_UDP_L4 dodgy bit set - dsa: mv88e6xxx: do a final check before timing out when polling - nf_tables: fix sleep in atomic in nft_chain_validate Previous releases - always broken: - sched: fix undoing tcf_bind_filter() in multiple classifiers - bpf, arm64: fix BTI type used for freplace attached functions - can: gs_usb: fix time stamp counter initialization - nft_set_pipapo: fix improper element removal (leading to UAF) Misc: - net: support STP on bridge in non-root netns, STP prevents packet loops so not supporting it results in freezing systems of unsuspecting users, and in turn very upset noises being made - fix kdoc warnings - annotate various bits of TCP state to prevent data races" * tag 'net-6.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits) net: phy: prevent stale pointer dereference in phy_init() tcp: annotate data-races around fastopenq.max_qlen tcp: annotate data-races around icsk->icsk_user_timeout tcp: annotate data-races around tp->notsent_lowat tcp: annotate data-races around rskq_defer_accept tcp: annotate data-races around tp->linger2 tcp: annotate data-races around icsk->icsk_syn_retries tcp: annotate data-races around tp->keepalive_probes tcp: annotate data-races around tp->keepalive_intvl tcp: annotate data-races around tp->keepalive_time tcp: annotate data-races around tp->tsoffset tcp: annotate data-races around tp->tcp_tx_delay Bluetooth: MGMT: Use correct address for memcpy() Bluetooth: btusb: Fix bluetooth on Intel Macbook 2014 Bluetooth: SCO: fix sco_conn related locking and validity issues Bluetooth: hci_conn: return ERR_PTR instead of NULL when there is no link Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_remove_adv_monitor() Bluetooth: coredump: fix building with coredump disabled Bluetooth: ISO: fix iso_conn related locking and validity issues Bluetooth: hci_event: call disconnect callback before deleting conn ...
2023-07-18bpf: Repeat check_max_stack_depth for async callbacksKumar Kartikeya Dwivedi1-2/+19
While the check_max_stack_depth function explores call chains emanating from the main prog, which is typically enough to cover all possible call chains, it doesn't explore those rooted at async callbacks unless the async callback will have been directly called, since unlike non-async callbacks it skips their instruction exploration as they don't contribute to stack depth. It could be the case that the async callback leads to a callchain which exceeds the stack depth, but this is never reachable while only exploring the entry point from main subprog. Hence, repeat the check for the main subprog *and* all async callbacks marked by the symbolic execution pass of the verifier, as execution of the program may begin at any of them. Consider functions with following stack depths: main: 256 async: 256 foo: 256 main: rX = async bpf_timer_set_callback(...) async: foo() Here, async is not descended as it does not contribute to stack depth of main (since it is referenced using bpf_pseudo_func and not bpf_pseudo_call). However, when async is invoked asynchronously, it will end up breaching the MAX_BPF_STACK limit by calling foo. Hence, in addition to main, we also need to explore call chains beginning at all async callback subprogs in a program. Fixes: 7ddc80a476c2 ("bpf: Teach stack depth check about async callbacks.") Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2023-07-18bpf: Fix subprog idx logic in check_max_stack_depthKumar Kartikeya Dwivedi1-5/+6
The assignment to idx in check_max_stack_depth happens once we see a bpf_pseudo_call or bpf_pseudo_func. This is not an issue as the rest of the code performs a few checks and then pushes the frame to the frame stack, except the case of async callbacks. If the async callback case causes the loop iteration to be skipped, the idx assignment will be incorrect on the next iteration of the loop. The value stored in the frame stack (as the subprogno of the current subprog) will be incorrect. This leads to incorrect checks and incorrect tail_call_reachable marking. Save the target subprog in a new variable and only assign to idx once we are done with the is_async_cb check which may skip pushing of frame to the frame stack and subsequent stack depth checks and tail call markings. Fixes: 7ddc80a476c2 ("bpf: Teach stack depth check about async callbacks.") Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2023-07-18Merge tag 'mm-hotfixes-stable-2023-07-18-12-28' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull hotfixes from Andrew Morton: "Seven hotfixes, six of which are cc:stable and one of which addresses a post-6.5 issue" * tag 'mm-hotfixes-stable-2023-07-18-12-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: maple_tree: fix node allocation testing on 32 bit maple_tree: fix 32 bit mas_next testing selftests/mm: mkdirty: fix incorrect position of #endif maple_tree: set the node limit when creating a new root node mm/mlock: fix vma iterator conversion of apply_vma_lock_flags() prctl: move PR_GET_AUXV out of PR_MCE_KILL selftests/mm: give scripts execute permission
2023-07-17prctl: move PR_GET_AUXV out of PR_MCE_KILLMiguel Ojeda1-5/+5
Somehow PR_GET_AUXV got added into PR_MCE_KILL's switch when the patch was applied [1]. Thus move it out of the switch, to the place the patch added it. In the recently released v6.4 kernel some user could, in principle, be already using this feature by mapping the right page and passing the PR_GET_AUXV constant as a pointer: prctl(PR_MCE_KILL, PR_GET_AUXV, ...) So this does change the behavior for users. We could keep the bug since the other subcases in PR_MCE_KILL (PR_MCE_KILL_CLEAR and PR_MCE_KILL_SET) do not overlap. However, v6.4 may be recent enough (2 weeks old) that moving the lines (rather than just adding a new case) does not break anybody? Moreover, the documentation in man-pages was just committed today [2]. Link: https://lkml.kernel.org/r/[email protected] Fixes: ddc65971bb67 ("prctl: add PR_GET_AUXV to copy auxv to userspace") Link: https://lore.kernel.org/all/d81864a7f7f43bca6afa2a09fc2e850e4050ab42.1680611394.git.josh@joshtriplett.org/ [1] Link: https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/?id=8cf0c06bfd3c2b219b044d4151c96f0da50af9ad [2] Signed-off-by: Miguel Ojeda <[email protected]> Cc: Josh Triplett <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-07-17locking/rtmutex: Fix task->pi_waiters integrityPeter Zijlstra4-76/+155
Henry reported that rt_mutex_adjust_prio_check() has an ordering problem and puts the lie to the comment in [7]. Sharing the sort key between lock->waiters and owner->pi_waiters *does* create problems, since unlike what the comment claims, holding [L] is insufficient. Notably, consider: A / \ M1 M2 | | B C That is, task A owns both M1 and M2, B and C block on them. In this case a concurrent chain walk (B & C) will modify their resp. sort keys in [7] while holding M1->wait_lock and M2->wait_lock. So holding [L] is meaningless, they're different Ls. This then gives rise to a race condition between [7] and [11], where the requeue of pi_waiters will observe an inconsistent tree order. B C (holds M1->wait_lock, (holds M2->wait_lock, holds B->pi_lock) holds A->pi_lock) [7] waiter_update_prio(); ... [8] raw_spin_unlock(B->pi_lock); ... [10] raw_spin_lock(A->pi_lock); [11] rt_mutex_enqueue_pi(); // observes inconsistent A->pi_waiters // tree order Fixing this means either extending the range of the owner lock from [10-13] to [6-13], with the immediate problem that this means [6-8] hold both blocked and owner locks, or duplicating the sort key. Since the locking in chain walk is horrible enough without having to consider pi_lock nesting rules, duplicate the sort key instead. By giving each tree their own sort key, the above race becomes harmless, if C sees B at the old location, then B will correct things (if they need correcting) when it walks up the chain and reaches A. Fixes: fb00aca47440 ("rtmutex: Turn the plist into an rb-tree") Reported-by: Henry Wu <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Tested-by: Henry Wu <[email protected]> Link: https://lkml.kernel.org/r/20230707161052.GF2883469%40hirez.programming.kicks-ass.net
2023-07-16Merge tag 'sched_urgent_for_v6.5_rc2' of ↵Linus Torvalds3-10/+23
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Borislav Petkov: - Remove a cgroup from under a polling process properly - Fix the idle sibling selection * tag 'sched_urgent_for_v6.5_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/psi: use kernfs polling functions for PSI trigger polling sched/fair: Use recent_used_cpu to test p->cpus_ptr
2023-07-16Merge tag 'hardening-v6.5-rc2' of ↵Linus Torvalds1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening fixes from Kees Cook: - Remove LTO-only suffixes from promoted global function symbols (Yonghong Song) - Remove unused .text..refcount section from vmlinux.lds.h (Petr Pavlu) - Add missing __always_inline to sparc __arch_xchg() (Arnd Bergmann) - Claim maintainership of string routines * tag 'hardening-v6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: sparc: mark __arch_xchg() as __always_inline MAINTAINERS: Foolishly claim maintainership of string routines kallsyms: strip LTO-only suffixes from promoted global functions vmlinux.lds.h: Remove a reference to no longer used sections .text..refcount
2023-07-16Merge tag 'probes-fixes-v6.5-rc1-2' of ↵Linus Torvalds6-29/+24
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probe fixes from Masami Hiramatsu: - fprobe: Add a comment why fprobe will be skipped if another kprobe is running in fprobe_kprobe_handler(). - probe-events: Fix some issues related to fetch-arguments: - Fix double counting of the string length for user-string and symstr. This will require longer buffer in the array case. - Fix not to count error code (minus value) for the total used length in array argument. This makes the total used length shorter. - Fix to update dynamic used data size counter only if fetcharg uses the dynamic size data. This may mis-count the used dynamic data size and corrupt data. - Revert "tracing: Add "(fault)" name injection to kernel probes" because that did not work correctly with a bug, and we agreed the current '(fault)' output (instead of '"(fault)"' like a string) explains what happened more clearly. - Fix to record 0-length (means fault access) data_loc data in fetch function itself, instead of store_trace_args(). If we record an array of string, this will fix to save fault access data on each entry of the array correctly. * tag 'probes-fixes-v6.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if fails Revert "tracing: Add "(fault)" name injection to kernel probes" tracing/probes: Fix to update dynamic data counter if fetcharg uses it tracing/probes: Fix not to count error code to total length tracing/probes: Fix to avoid double count of the string length on the array fprobes: Add a comment why fprobe_kprobe_handler exits if kprobe is running
2023-07-14Merge tag 'pm-6.5-rc2' of ↵Linus Torvalds2-2/+8
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix hibernation (after recent changes), frequency QoS and the sparc cpufreq driver. Specifics: - Unbreak the /sys/power/resume interface after recent changes (Azat Khuzhin). - Allow PM_QOS_DEFAULT_VALUE to be used with frequency QoS (Chungkai Yang). - Remove __init from cpufreq callbacks in the sparc driver, because they may be called after initialization too (Viresh Kumar)" * tag 'pm-6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: sparc: Don't mark cpufreq callbacks with __init PM: QoS: Restore support for default value on frequency QoS PM: hibernate: Fix writing maj:min to /sys/power/resume
2023-07-14Merge branches 'pm-sleep' and 'pm-qos'Rafael J. Wysocki2-2/+8
Merge a PM QoS fix and a hibernation fix for 6.5-rc2. - Unbreak the /sys/power/resume interface after recent changes (Azat Khuzhin). - Allow PM_QOS_DEFAULT_VALUE to be used with frequency QoS (Chungkai Yang). * pm-sleep: PM: hibernate: Fix writing maj:min to /sys/power/resume * pm-qos: PM: QoS: Restore support for default value on frequency QoS
2023-07-14tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if ↵Masami Hiramatsu (Google)3-12/+14
fails Fix to record 0-length data to data_loc in fetch_store_string*() if it fails to get the string data. Currently those expect that the data_loc is updated by store_trace_args() if it returns the error code. However, that does not work correctly if the argument is an array of strings. In that case, store_trace_args() only clears the first entry of the array (which may have no error) and leaves other entries. So it should be cleared by fetch_store_string*() itself. Also, 'dyndata' and 'maxlen' in store_trace_args() should be updated only if it is used (ret > 0 and argument is a dynamic data.) Link: https://lore.kernel.org/all/168908496683.123124.4761206188794205601.stgit@devnote2/ Fixes: 40b53b771806 ("tracing: probeevent: Add array type support") Cc: [email protected] Reviewed-by: Steven Rostedt (Google) <[email protected]> Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
2023-07-13Merge tag 'net-6.5-rc2' of ↵Linus Torvalds2-18/+27
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from netfilter, wireless and ebpf. Current release - regressions: - netfilter: conntrack: gre: don't set assured flag for clash entries - wifi: iwlwifi: remove 'use_tfh' config to fix crash Previous releases - regressions: - ipv6: fix a potential refcount underflow for idev - icmp6: ifix null-ptr-deref of ip6_null_entry->rt6i_idev in icmp6_dev() - bpf: fix max stack depth check for async callbacks - eth: mlx5e: - check for NOT_READY flag state after locking - fix page_pool page fragment tracking for XDP - eth: igc: - fix tx hang issue when QBV gate is closed - fix corner cases for TSN offload - eth: octeontx2-af: Move validation of ptp pointer before its usage - eth: ena: fix shift-out-of-bounds in exponential backoff Previous releases - always broken: - core: prevent skb corruption on frag list segmentation - sched: - cls_fw: fix improper refcount update leads to use-after-free - sch_qfq: account for stab overhead in qfq_enqueue - netfilter: - report use refcount overflow - prevent OOB access in nft_byteorder_eval - wifi: mt7921e: fix init command fail with enabled device - eth: ocelot: fix oversize frame dropping for preemptible TCs - eth: fec: recycle pages for transmitted XDP frames" * tag 'net-6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (79 commits) selftests: tc-testing: add test for qfq with stab overhead net/sched: sch_qfq: account for stab overhead in qfq_enqueue selftests: tc-testing: add tests for qfq mtu sanity check net/sched: sch_qfq: reintroduce lmax bound check for MTU wifi: cfg80211: fix receiving mesh packets without RFC1042 header wifi: rtw89: debug: fix error code in rtw89_debug_priv_send_h2c_set() net: txgbe: fix eeprom calculation error net/sched: make psched_mtu() RTNL-less safe net: ena: fix shift-out-of-bounds in exponential backoff netdevsim: fix uninitialized data in nsim_dev_trap_fa_cookie_write() net/sched: flower: Ensure both minimum and maximum ports are specified MAINTAINERS: Add another mailing list for QUALCOMM ETHQOS ETHERNET DRIVER docs: netdev: update the URL of the status page wifi: iwlwifi: remove 'use_tfh' config to fix crash xdp: use trusted arguments in XDP hints kfuncs bpf: cpumap: Fix memory leak in cpu_map_update_elem wifi: airo: avoid uninitialized warning in airo_get_rate() octeontx2-pf: Add additional check for MCAM rules net: dsa: Removed unneeded of_node_put in felix_parse_ports_node net: fec: use netdev_err_once() instead of netdev_err() ...
2023-07-13Merge tag 'trace-v6.5-rc1-3' of ↵Linus Torvalds8-30/+81
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix some missing-prototype warnings - Fix user events struct args (did not include size of struct) When creating a user event, the "struct" keyword is to denote that the size of the field will be passed in. But the parsing failed to handle this case. - Add selftest to struct sizes for user events - Fix sample code for direct trampolines. The sample code for direct trampolines attached to handle_mm_fault(). But the prototype changed and the direct trampoline sample code was not updated. Direct trampolines needs to have the arguments correct otherwise it can fail or crash the system. - Remove unused ftrace_regs_caller_ret() prototype. - Quiet false positive of FORTIFY_SOURCE Due to backward compatibility, the structure used to save stack traces in the kernel had a fixed size of 8. This structure is exported to user space via the tracing format file. A change was made to allow more than 8 functions to be recorded, and user space now uses the size field to know how many functions are actually in the stack. But the structure still has size of 8 (even though it points into the ring buffer that has the required amount allocated to hold a full stack. This was fine until the fortifier noticed that the memcpy(&entry->caller, stack, size) was greater than the 8 functions and would complain at runtime about it. Hide this by using a pointer to the stack location on the ring buffer instead of using the address of the entry structure caller field. - Fix a deadloop in reading trace_pipe that was caused by a mismatch between ring_buffer_empty() returning false which then asked to read the data, but the read code uses rb_num_of_entries() that returned zero, and causing a infinite "retry". - Fix a warning caused by not using all pages allocated to store ftrace functions, where this can happen if the linker inserts a bunch of "NULL" entries, causing the accounting of how many pages needed to be off. - Fix histogram synthetic event crashing when the start event is removed and the end event is still using a variable from it - Fix memory leak in freeing iter->temp in tracing_release_pipe() * tag 'trace-v6.5-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix memory leak of iter->temp when reading trace_pipe tracing/histograms: Add histograms to hist_vars if they have referenced variables tracing: Stop FORTIFY_SOURCE complaining about stack trace caller ftrace: Fix possible warning on checking all pages used in ftrace_process_locs() ring-buffer: Fix deadloop issue on reading trace_pipe tracing: arm64: Avoid missing-prototype warnings selftests/user_events: Test struct size match cases tracing/user_events: Fix struct arg size match check x86/ftrace: Remove unsued extern declaration ftrace_regs_caller_ret() arm64: ftrace: Add direct call trampoline samples support samples: ftrace: Save required argument registers in sample trampolines
2023-07-14Revert "tracing: Add "(fault)" name injection to kernel probes"Masami Hiramatsu (Google)3-26/+9
This reverts commit 2e9906f84fc7c99388bb7123ade167250d50f1c0. It was turned out that commit 2e9906f84fc7 ("tracing: Add "(fault)" name injection to kernel probes") did not work correctly and probe events still show just '(fault)' (instead of '"(fault)"'). Also, current '(fault)' is more explicit that it faulted. This also moves FAULT_STRING macro to trace.h so that synthetic event can keep using it, and uses it in trace_probe.c too. Link: https://lore.kernel.org/all/168908495772.123124.1250788051922100079.stgit@devnote2/ Link: https://lore.kernel.org/all/[email protected]/ Cc: [email protected] Cc: Andrew Morton <[email protected]> Cc: Tom Zanussi <[email protected]> Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-14tracing/probes: Fix to update dynamic data counter if fetcharg uses itMasami Hiramatsu (Google)1-5/+7
Fix to update dynamic data counter ('dyndata') and max length ('maxlen') only if the fetcharg uses the dynamic data. Also get out arg->dynamic from unlikely(). This makes dynamic data address wrong if process_fetch_insn() returns error on !arg->dynamic case. Link: https://lore.kernel.org/all/168908494781.123124.8160245359962103684.stgit@devnote2/ Suggested-by: Steven Rostedt <[email protected]> Link: https://lore.kernel.org/all/[email protected]/ Fixes: 9178412ddf5a ("tracing: probeevent: Return consumed bytes of dynamic area") Cc: [email protected] Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-14tracing/probes: Fix not to count error code to total lengthMasami Hiramatsu (Google)1-0/+2
Fix not to count the error code (which is minus value) to the total used length of array, because it can mess up the return code of process_fetch_insn_bottom(). Also clear the 'ret' value because it will be used for calculating next data_loc entry. Link: https://lore.kernel.org/all/168908493827.123124.2175257289106364229.stgit@devnote2/ Reported-by: Dan Carpenter <[email protected]> Closes: https://lore.kernel.org/all/[email protected]/ Fixes: 9b960a38835f ("tracing: probeevent: Unify fetch_insn processing common part") Cc: [email protected] Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-14tracing/probes: Fix to avoid double count of the string length on the arrayMasami Hiramatsu (Google)1-2/+2
If an array is specified with the ustring or symstr, the length of the strings are accumlated on both of 'ret' and 'total', which means the length is double counted. Just set the length to the 'ret' value for avoiding double counting. Link: https://lore.kernel.org/all/168908492917.123124.15076463491122036025.stgit@devnote2/ Reported-by: Dan Carpenter <[email protected]> Closes: https://lore.kernel.org/all/[email protected]/ Fixes: 88903c464321 ("tracing/probe: Add ustring type for user-space string") Cc: [email protected] Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>
2023-07-14fprobes: Add a comment why fprobe_kprobe_handler exits if kprobe is runningMasami Hiramatsu (Google)1-0/+6
Add a comment the reason why fprobe_kprobe_handler() exits if any other kprobe is running. Link: https://lore.kernel.org/all/168874788299.159442.2485957441413653858.stgit@devnote2/ Suggested-by: Steven Rostedt <[email protected]> Link: https://lore.kernel.org/all/[email protected]/ Signed-off-by: Masami Hiramatsu (Google) <[email protected]> Reviewed-by: Steven Rostedt (Google) <[email protected]>