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2020-07-04arch: rename copy_thread_tls() back to copy_thread()Christian Brauner1-1/+1
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls() back simply copy_thread(). It's a simpler name, and doesn't imply that only tls is copied here. This finishes an outstanding chunk of internal process creation work since we've added clone3(). Cc: [email protected] Acked-by: Thomas Bogendoerfer <[email protected]>A Acked-by: Stafford Horne <[email protected]> Acked-by: Greentime Hu <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]>A Reviewed-by: Kees Cook <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2020-06-17maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofaultChristoph Hellwig1-1/+1
Better describe what these functions do. Suggested-by: Linus Torvalds <[email protected]> Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09maccess: always use strict semantics for probe_kernel_readChristoph Hellwig1-1/+1
Except for historical confusion in the kprobes/uprobes and bpf tracers, which has been fixed now, there is no good reason to ever allow user memory accesses from probe_kernel_read. Switch probe_kernel_read to only read from kernel memory. [[email protected]: update it for "mm, dump_page(): do not crash with invalid mapping pointer"] Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09maccess: unify the probe kernel arch hooksChristoph Hellwig1-6/+4
Currently architectures have to override every routine that probes kernel memory, which includes a pure read and strcpy, both in strict and not strict variants. Just provide a single arch hooks instead to make sure all architectures cover all the cases. [[email protected]: fix !CONFIG_X86_64 build] Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse2-2/+2
Convert comments that reference mmap_sem to reference mmap_lock instead. [[email protected]: fix up linux-next leftovers] [[email protected]: s/lockaphore/lock/, per Vlastimil] [[email protected]: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Reviewed-by: Daniel Jordan <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: David Rientjes <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: John Hubbard <[email protected]> Cc: Laurent Dufour <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ying Han <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse2-4/+4
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Daniel Jordan <[email protected]> Reviewed-by: Laurent Dufour <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: David Rientjes <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: John Hubbard <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ying Han <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mm: pgtable: add shortcuts for accessing kernel PMD and PTEMike Rapoport2-16/+2
The powerpc 32-bit implementation of pgtable has nice shortcuts for accessing kernel PMD and PTE for a given virtual address. Make these helpers available for all architectures. [[email protected]: microblaze: fix page table traversal in setup_rt_frame()] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: s/pmd_ptr_k/pmd_off_k/ in various powerpc places] Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Cain <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chris Zankel <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Nick Hu <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vincent Chen <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yoshinori Sato <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport6-6/+0
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Cain <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chris Zankel <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nick Hu <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vincent Chen <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yoshinori Sato <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09kernel: rename show_stack_loglvl() => show_stack()Dmitry Safonov1-6/+1
Now the last users of show_stack() got converted to use an explicit log level, show_stack_loglvl() can drop it's redundant suffix and become once again well known show_stack(). Signed-off-by: Dmitry Safonov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09um: add show_stack_loglvl()Dmitry Safonov1-8/+16
Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). [1]: https://lore.kernel.org/lkml/[email protected]/T/#u Signed-off-by: Dmitry Safonov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Richard Weinberger <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09um/sysrq: remove needless variable spDmitry Safonov1-3/+1
`sp' is a needless excercise here. Signed-off-by: Dmitry Safonov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Richard Weinberger <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-04Merge branch 'for-linus' of ↵Linus Torvalds1-0/+16
git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching Pull livepatching updates from Jiri Kosina: - simplifications and improvements for issues Peter Ziljstra found during his previous work on W^X cleanups. This allows us to remove livepatch arch-specific .klp.arch sections and add proper support for jump labels in patched code. Also, this patchset removes the last module_disable_ro() usage in the tree. Patches from Josh Poimboeuf and Peter Zijlstra - a few other minor cleanups * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching: MAINTAINERS: add lib/livepatch to LIVE PATCHING livepatch: add arch-specific headers to MAINTAINERS livepatch: Make klp_apply_object_relocs static MAINTAINERS: adjust to livepatch .klp.arch removal module: Make module_enable_ro() static again x86/module: Use text_mutex in apply_relocate_add() module: Remove module_disable_ro() livepatch: Remove module_disable_ro() usage x86/module: Use text_poke() for late relocations s390/module: Use s390_kernel_write() for late relocations s390: Change s390_kernel_write() return type to match memcpy() livepatch: Prevent module-specific KLP rela sections from referencing vmlinux symbols livepatch: Remove .klp.arch livepatch: Apply vmlinux-specific KLP relocations early livepatch: Disallow vmlinux.ko
2020-06-03mm: free_area_init: use maximal zone PFNs rather than zone sizesMike Rapoport1-8/+4
Currently, architectures that use free_area_init() to initialize memory map and node and zone structures need to calculate zone and hole sizes. We can use free_area_init_nodes() instead and let it detect the zone boundaries while the architectures will only have to supply the possible limits for the zones. Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Tested-by: Hoan Tran <[email protected]> [arm64] Reviewed-by: Baoquan He <[email protected]> Cc: Brian Cain <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Michal Simek <[email protected]> Cc: Nick Hu <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Yoshinori Sato <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-05-08x86/module: Use text_poke() for late relocationsPeter Zijlstra1-0/+16
Because of late module patching, a livepatch module needs to be able to apply some of its relocations well after it has been loaded. Instead of playing games with module_{dis,en}able_ro(), use existing text poking mechanisms to apply relocations after module loading. So far only x86, s390 and Power have HAVE_LIVEPATCH but only the first two also have STRICT_MODULE_RWX. This will allow removal of the last module_disable_ro() usage in livepatch. The ultimate goal is to completely disallow making executable mappings writable. [ jpoimboe: Split up patches. Use mod state to determine whether memcpy() can be used. Implement text_poke() for UML. ] Cc: [email protected] Suggested-by: Josh Poimboeuf <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Joe Lawrence <[email protected]> Acked-by: Miroslav Benes <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
2020-04-29um: syscall.c: include <asm/unistd.h>Johannes Berg1-0/+1
Without CONFIG_SECCOMP, we don't get this include recursively through the existing includes, thus failing the build on not having __NR_syscall_max defined. Add the necessary include to fix this. Signed-off-by: Johannes Berg <[email protected]> Acked-By: Anton Ivanov <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-04-07Merge tag 'for-linus-5.7-rc1' of ↵Linus Torvalds5-65/+528
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: - New mode for time travel, external via virtio - Fixes for ubd to make sure no requests can get lost - Fixes for vector networking - Allow CONFIG_STATIC_LINK only when possible - Minor cleanups and fixes * tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: Remove some unnecessary NULL checks in vector_user.c um: vector: Avoid NULL ptr deference if transport is unset um: Make CONFIG_STATIC_LINK actually static um: Implement cpu_relax() as ndelay(1) for time-travel um: Implement ndelay/udelay in time-travel mode um: Implement time-travel=ext um: virtio: Implement VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS um: time-travel: Rewrite as an event scheduler um: Move timer-internal.h to non-shared hostfs: Use kasprintf() instead of fixed buffer formatting um: falloc.h needs to be directly included for older libc um: ubd: Retry buffer read on any kind of error um: ubd: Prevent buffer overrun on command completion um: Fix overlapping ELF segments when statically linked um: Delete never executed timer um: Don't overwrite ethtool driver version um: Fix len of file in create_pid_file um: Don't use console_drivers directly um: Cleanup CONFIG_IOSCHED_CFQ
2020-04-02mm: allow VM_FAULT_RETRY for multiple timesPeter Xu1-1/+0
The idea comes from a discussion between Linus and Andrea [1]. Before this patch we only allow a page fault to retry once. We achieved this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing handle_mm_fault() the second time. This was majorly used to avoid unexpected starvation of the system by looping over forever to handle the page fault on a single page. However that should hardly happen, and after all for each code path to return a VM_FAULT_RETRY we'll first wait for a condition (during which time we should possibly yield the cpu) to happen before VM_FAULT_RETRY is really returned. This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY flag when we receive VM_FAULT_RETRY. It means that the page fault handler now can retry the page fault for multiple times if necessary without the need to generate another page fault event. Meanwhile we still keep the FAULT_FLAG_TRIED flag so page fault handler can still identify whether a page fault is the first attempt or not. Then we'll have these combinations of fault flags (only considering ALLOW_RETRY flag and TRIED flag): - ALLOW_RETRY and !TRIED: this means the page fault allows to retry, and this is the first try - ALLOW_RETRY and TRIED: this means the page fault allows to retry, and this is not the first try - !ALLOW_RETRY and !TRIED: this means the page fault does not allow to retry at all - !ALLOW_RETRY and TRIED: this is forbidden and should never be used In existing code we have multiple places that has taken special care of the first condition above by checking against (fault_flags & FAULT_FLAG_ALLOW_RETRY). This patch introduces a simple helper to detect the first retry of a page fault by checking against both (fault_flags & FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now even the 2nd try will have the ALLOW_RETRY set, then use that helper in all existing special paths. One example is in __lock_page_or_retry(), now we'll drop the mmap_sem only in the first attempt of page fault and we'll keep it in follow up retries, so old locking behavior will be retained. This will be a nice enhancement for current code [2] at the same time a supporting material for the future userfaultfd-writeprotect work, since in that work there will always be an explicit userfault writeprotect retry for protected pages, and if that cannot resolve the page fault (e.g., when userfaultfd-writeprotect is used in conjunction with swapped pages) then we'll possibly need a 3rd retry of the page fault. It might also benefit other potential users who will have similar requirement like userfault write-protection. GUP code is not touched yet and will be covered in follow up patch. Please read the thread below for more information. [1] https://lore.kernel.org/lkml/[email protected]/ [2] https://lore.kernel.org/lkml/[email protected]/ Suggested-by: Linus Torvalds <[email protected]> Suggested-by: Andrea Arcangeli <[email protected]> Signed-off-by: Peter Xu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Tested-by: Brian Geffon <[email protected]> Cc: Bobby Powers <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Denis Plotnikov <[email protected]> Cc: "Dr . David Alan Gilbert" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: "Kirill A . Shutemov" <[email protected]> Cc: Martin Cracauer <[email protected]> Cc: Marty McFadden <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Maya Gokhale <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Pavel Emelyanov <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-02mm: introduce FAULT_FLAG_DEFAULTPeter Xu1-1/+1
Although there're tons of arch-specific page fault handlers, most of them are still sharing the same initial value of the page fault flags. Say, merely all of the page fault handlers would allow the fault to be retried, and they also allow the fault to respond to SIGKILL. Let's define a default value for the fault flags to replace those initial page fault flags that were copied over. With this, it'll be far easier to introduce new fault flag that can be used by all the architectures instead of touching all the archs. Signed-off-by: Peter Xu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Tested-by: Brian Geffon <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Bobby Powers <[email protected]> Cc: Denis Plotnikov <[email protected]> Cc: "Dr . David Alan Gilbert" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: "Kirill A . Shutemov" <[email protected]> Cc: Martin Cracauer <[email protected]> Cc: Marty McFadden <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Maya Gokhale <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Pavel Emelyanov <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-03-29um: Implement ndelay/udelay in time-travel modeJohannes Berg1-0/+6
In external or inf-cpu time-travel mode, ndelay/udelay currently just waste CPU time since the simulation time doesn't advance. Implement them properly in this case. Note that the "if (time_travel_mode == ...)" parts compile out if CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, time_travel_mode is defined to TT_MODE_OFF in that case. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-03-29um: Implement time-travel=extJohannes Berg2-13/+313
This implements synchronized time-travel mode which - using a special application on a unix socket - lets multiple machines take part in a time-travelling simulation together. The protocol for the unix domain socket is defined in the new file include/uapi/linux/um_timetravel.h. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-03-29um: time-travel: Rewrite as an event schedulerJohannes Berg2-50/+208
Instead of tracking all the various timer configurations, modify the time-travel mode to have an event scheduler and use a timer event on the scheduler to handle the different timer configurations. This doesn't change the function right now, but it prepares the code for having different kinds of events in the future (i.e. interrupts coming from other devices that are part of co-simulation.) While at it, also move time_travel_sleep() to time.c to reduce the externally visible API surface. Also, we really should mark time-travel as incompatible with SMP, even if UML doesn't support SMP yet. Finally, I noticed a bug while developing this - if we move time forward due to consuming time while reading the clock, we might move across the next event and that would cause us to go backward in time when we then handle that event. Fix that by invoking the whole event machine in this case, but in order to simplify this, make reading the clock only cost something when interrupts are not disabled. Otherwise, we'd have to hook into the interrupt delivery machinery etc. and that's somewhat intrusive. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-03-29um: Move timer-internal.h to non-sharedJohannes Berg3-3/+3
This file isn't really shared, it's only used on the kernel side, not on the user side. Remove the include from the user-side and move the file to a better place. While at it, rename it to time-internal.h, it's not really just timers but all kinds of things related to timekeeping. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-03-29um: Fix overlapping ELF segments when statically linkedDavid Gow1-1/+1
When statically linked, the .text section in UML kernels is not page aligned, causing it to share a page with the executable headers. As .text and the executable headers have different permissions, this causes the kernel to wish to map the same page twice (once as headers with r-- permissions, once as .text with r-x permissions), causing a segfault, and a nasty message printed to the host kernel's dmesg: "Uhuuh, elf segment at 0000000060000000 requested but the memory is mapped already" By aligning the .text to a page boundary (as in the dynamically linked version in dyn.lds.S), there is no such overlap, and the kernel runs correctly. Signed-off-by: David Gow <[email protected]> Reviewed-by: Brendan Higgins <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-03-29um: Don't use console_drivers directlyAndy Shevchenko1-5/+4
console_drivers is kind of (semi-)private variable to the console code. Direct use of it make us stuck with it being exported here and there. Reduce use of console_drivers by replacing it with for_each_console(). Cc: Thomas Meyer <[email protected]> Signed-off-by: Andy Shevchenko <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-02-04proc: convert everything to "struct proc_ops"Alexey Dobriyan2-16/+14
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in seq_file.h. Conversion rule is: llseek => proc_lseek unlocked_ioctl => proc_ioctl xxx => proc_xxx delete ".owner = THIS_MODULE" line [[email protected]: fix drivers/isdn/capi/kcapi_proc.c] [[email protected]: fix kernel/sched/psi.c] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2 Signed-off-by: Alexey Dobriyan <[email protected]> Signed-off-by: Stephen Rothwell <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-01-19Revert "um: Enable CONFIG_CONSTRUCTORS"Johannes Berg1-0/+1
This reverts commit 786b2384bf1c ("um: Enable CONFIG_CONSTRUCTORS"). There are two issues with this commit, uncovered by Anton in tests on some (Debian) systems: 1) I completely forgot to call any constructors if CONFIG_CONSTRUCTORS isn't set. Don't recall now if it just wasn't needed on my system, or if I never tested this case. 2) With that fixed, it works - with CONFIG_CONSTRUCTORS *unset*. If I set CONFIG_CONSTRUCTORS, it fails again, which isn't totally unexpected since whatever wanted to run is likely to have to run before the kernel init etc. that calls the constructors in this case. Basically, some constructors that gcc emits (libc has?) need to run very early during init; the failure mode otherwise was that the ptrace fork test already failed: ---------------------- $ ./linux mem=512M Core dump limits : soft - 0 hard - NONE Checking that ptrace can change system call numbers...check_ptrace : child exited with exitcode 6, while expecting 0; status 0x67f Aborted ---------------------- Thinking more about this, it's clear that we simply cannot support CONFIG_CONSTRUCTORS in UML. All the cases we need now (gcov, kasan) involve not use of the __attribute__((constructor)), but instead some constructor code/entry generated by gcc. Therefore, we cannot distinguish between kernel constructors and system constructors. Thus, revert this commit. Cc: [email protected] [5.4+] Fixes: 786b2384bf1c ("um: Enable CONFIG_CONSTRUCTORS") Reported-by: Anton Ivanov <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Acked-by: Anton Ivanov <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2020-01-07um: Implement copy_thread_tlsAmanieu d'Antras1-3/+3
This is required for clone3 which passes the TLS value through a struct rather than a register. Signed-off-by: Amanieu d'Antras <[email protected]> Cc: [email protected] Cc: <[email protected]> # 5.3.x Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Christian Brauner <[email protected]>
2019-12-04um: add support for folded p4d page tablesMike Rapoport5-12/+75
The UML port uses 4 and 5 level fixups to support higher level page table directories in the generic VM code. Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate and drop usage of __ARCH_USE_5LEVEL_HACK. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Cc: Anatoly Pugachev <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Helge Deller <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jeff Dike <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michal Simek <[email protected]> Cc: Peter Rosin <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rolf Eike Beer <[email protected]> Cc: Russell King <[email protected]> Cc: Russell King <[email protected]> Cc: Sam Creasey <[email protected]> Cc: Vincent Chen <[email protected]> Cc: Vineet Gupta <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-12-04um: remove unused pxx_offset_proc() and addr_pte() functionsMike Rapoport1-29/+0
The pxx_offset_proc() and addr_pte() functions are never used. Remove them. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Acked-by: Richard Weinberger <[email protected]> Cc: Anatoly Pugachev <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Helge Deller <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jeff Dike <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michal Simek <[email protected]> Cc: Peter Rosin <[email protected]> Cc: Rolf Eike Beer <[email protected]> Cc: Russell King <[email protected]> Cc: Russell King <[email protected]> Cc: Sam Creasey <[email protected]> Cc: Vincent Chen <[email protected]> Cc: Vineet Gupta <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-10-10seccomp: simplify secure_computing()Christian Brauner1-1/+1
Afaict, the struct seccomp_data argument to secure_computing() is unused by all current callers. So let's remove it. The argument was added in [1]. It was added because having the arch supply the syscall arguments used to be faster than having it done by secure_computing() (cf. Andy's comment in [2]). This is not true anymore though. /* References */ [1]: 2f275de5d1ed ("seccomp: Add a seccomp_data parameter secure_computing()") [2]: https://lore.kernel.org/r/CALCETrU_fs_At-hTpr231kpaAd0z7xJN4ku-DvzhRU6cvcJA_w@mail.gmail.com Signed-off-by: Christian Brauner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Drewry <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Acked-by: Borislav Petkov <[email protected]> Acked-by: Andy Lutomirski <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Kees Cook <[email protected]>
2019-09-16um: irq: Fix LAST_IRQ usage in init_IRQ()Erel Geron1-1/+1
LAST_IRQ was used incorrectly in init_IRQ. Commit 09ccf0364ca3 forgot to update the for loop. Fix this. Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver") Fixes: 09ccf0364ca3 ("um: Fix off by one error in IRQ enumeration") Signed-off-by: Erel Geron <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Acked-by: Anton Ivanov <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: Add SPDX headers to files in arch/um/kernel/Alex Dewar28-29/+29
Convert files to use SPDX header. All files are licensed under the GPLv2. Signed-off-by: Alex Dewar <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: drivers: Add virtio vhost-user driverErel Geron4-0/+5
This module allows virtio devices to be used over a vhost-user socket. Signed-off-by: Erel Geron <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: time-travel: Restrict time update in IRQ handlerJohannes Berg2-4/+15
We currently do the time updates in the timer handler, even if we just call the timer handler ourselves. In basic mode we must in fact do it there since otherwise the OS timer signal won't move time forward, but in inf-cpu mode we don't need to, and it's harder to understand. Restrict the update there to basic mode, adding a comment, and do it before calling the timer_handler() in inf-cpu mode. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: time-travel: Fix periodic timersJohannes Berg2-1/+7
Periodic timers are broken, because the also only fire once. As it happens, Linux doesn't care because it only sets the timer to periodic very briefly during boot, and then switches it only between one-shot and off later. Nevertheless, fix the logic (we shouldn't even be looking at time_travel_timer_expiry unless the timer is enabled) and change the code to fire the timer periodically in periodic mode, in case it ever gets used in the future. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: Enable CONFIG_CONSTRUCTORSJohannes Berg1-1/+0
We do need to call the constructors for *modules*, and at least for KASAN in the future, we must call even the kernel constructors only later when the kernel has been initialized. Instead of relying on libc to call them, emit an empty section for libc and let the kernel's CONSTRUCTORS code do the rest of the job. Tested that it indeed doesn't work in modules, and does work after the fixes in both, with a few functions with __attribute__((constructor)) in both dynamic and static builds. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: Place (soft)irq text with macrosJohannes Berg2-0/+4
Otherwise it gets placed without the start/end markers. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: Implement TRACE_IRQFLAGS_SUPPORTJohannes Berg3-3/+31
UML enables TRACE_IRQFLAGS_SUPPORT but doesn't actually implement it. It seems to have been added for lockdep support, but that can't actually really work well without IRQ flags tracing, as is also very noisily reported when enabling CONFIG_DEBUG_LOCKDEP. Implement it now. Fixes: 711553efa5b8 ("[PATCH] uml: declare in Kconfig our partial LOCKDEP support") Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-09-15um: Remove meaningless clearing of clean-filesMasahiro Yamada1-1/+0
Signed-off-by: Masahiro Yamada <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-08-23um: fix time travel modeJohannes Berg2-8/+10
Unfortunately, my build fix for when time travel mode isn't enabled broke time travel mode, because I forgot that we need to use the timer time after the timer has been marked disabled, and thus need to leave the time stored instead of zeroing it. Fix that by splitting the inline into two, so we can call only the _mode() one in the relevant code path. Fixes: b482e48d29f1 ("um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT") Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-14Merge tag 'for-linus-5.3-rc1' of ↵Linus Torvalds5-12/+183
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: - A new timer mode, time travel, for testing with UML - Many bugixes/improvements for the serial line driver - Various bugfixes * tag 'for-linus-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT um: Fix kcov crash during startup um: configs: Remove useless UEVENT_HELPER_PATH um: Support time travel mode um: Pass nsecs to os timer functions um: Remove drivers/ssl.h um: Don't garbage collect in deactivate_all_fds() um: Silence lockdep complaint about mmap_sem um: Remove locking in deactivate_all_fds() um: Timer code cleanup um: fix os_timer_one_shot() um: Fix IRQ controller regression on console read
2019-07-12um: switch to generic version of pte allocationMike Rapoport1-22/+0
um allocates PTE pages with __get_free_page() and uses GFP_KERNEL | __GFP_ZERO for the allocations. Switch it to the generic version that does exactly the same thing for the kernel page tables and adds __GFP_ACCOUNT for the user PTEs. The pte_free() and pte_free_kernel() versions are identical to the generic ones and can be simply dropped. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Reviewed-by: Anton Ivanov <[email protected]> Acked-by: Anton Ivanov <[email protected]> Cc: Albert Ou <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Paul Burton <[email protected]> Cc: Ralf Baechle <[email protected]> Cc: Richard Kuo <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Russell King <[email protected]> Cc: Sam Creasey <[email protected]> Cc: Vincent Chen <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-07-08Merge branch 'siginfo-linus' of ↵Linus Torvalds5-18/+13
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...
2019-07-04um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORTJohannes Berg1-1/+1
When CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, the build was broken. Fix this. Fixes: 065038706f77 ("um: Support time travel mode") Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Fix kcov crash during startupMarek Majkowski1-0/+2
Kcov fails to start when compiled with kcov. Disable KCOV on arch/uml/kernel/skas. $ gdb -q -ex r ./vmlinux Program received signal SIGSEGV, Segmentation fault. check_kcov_mode (t=<>, needed_mode=<>) at kernel/kcov.c:70 70 mode = READ_ONCE(t->kcov_mode); Signed-off-by: Marek Majkowski <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Support time travel modeJohannes Berg3-7/+175
Sometimes it can be useful to run with "time travel" inside the UML instance, for example for testing. For example, some tests for the wireless subsystem and userspace are based on hwsim, a virtual wireless adapter. Some tests can take a long time to run because they e.g. wait for 120 seconds to elapse for some regulatory checks. This obviously goes faster if it need not actually wait that long, but time inside the test environment just "bumps up" when there's nothing to do. Add CONFIG_UML_TIME_TRAVEL_SUPPORT to enable code to support such modes at runtime, selected on the command line: * just "time-travel", in which time inside the UML instance can move faster than real time, if there's nothing to do * "time-travel=inf-cpu" in which time also moves slower and any CPU processing takes no time at all, which allows to implement consistent behaviour regardless of host CPU load (or speed) or debug overhead. An additional "time-travel-start=<seconds>" parameter is also supported in this case to start the wall clock at this time (in unix epoch). With this enabled, the test mentioned above goes from a runtime of about 140 seconds (with startup overhead and all) to being CPU bound and finishing in 15 seconds (on my slow laptop). Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Pass nsecs to os timer functionsJohannes Berg1-2/+2
This makes the code clearer and lets the time travel patch have the actual time used for these functions in just one place. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Don't garbage collect in deactivate_all_fds()Johannes Berg1-1/+1
My previous commit didn't actually address the whole issue with lockdep shutdown, I had another local modification that disabled lockdep but that wasn't sufficient alone, so had to do the other change. Another issue remained though - during kfree() we acquire locks and lockdep tries to annotate those with exactly the same issue in the other patch - we no longer have "current". So, just remove the garbage collection. There's no value in it anyway since we're going to shut down anyway and marking a slab object as free is now not very useful anymore. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Remove locking in deactivate_all_fds()Johannes Berg1-3/+0
Not only does the locking contradict the comment, and as the comment says is pointless and actually harmful (all the actual OS threads have exited already), but it also causes crashes when lockdep is enabled, because calling into the spinlock calls into lockdep, which then tries to determine the current task, which no longer exists. Remove the locking to let UML shut down cleanly in case lockdep is enabled. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>
2019-07-02um: Timer code cleanupJohannes Berg1-2/+2
There are some unused functions, and some others that have unused arguments; clean up the timer code a bit. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Richard Weinberger <[email protected]>