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2018-08-30perf probe powerpc: Ignore SyS symbols irrespective of endiannessSandipan Das1-1/+3
This makes sure that the SyS symbols are ignored for any powerpc system, not just the big endian ones. Reported-by: Naveen N. Rao <[email protected]> Signed-off-by: Sandipan Das <[email protected]> Reviewed-by: Kamalesh Babulal <[email protected]> Acked-by: Naveen N. Rao <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Ravi Bangoria <[email protected]> Fixes: fb6d59423115 ("perf probe ppc: Use the right prefix when ignoring SyS symbols on ppc") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30vfs: implement readahead(2) using POSIX_FADV_WILLNEEDAmir Goldstein3-30/+21
The implementation of readahead(2) syscall is identical to that of fadvise64(POSIX_FADV_WILLNEED) with a few exceptions: 1. readahead(2) returns -EINVAL for !mapping->a_ops and fadvise64() ignores the request and returns 0. 2. fadvise64() checks for integer overflow corner case 3. fadvise64() calls the optional filesystem fadvise() file operation Unite the two implementations by calling vfs_fadvise() from readahead(2) syscall. Check the !mapping->a_ops in readahead(2) syscall to preserve documented syscall ABI behaviour. Suggested-by: Miklos Szeredi <[email protected]> Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>
2018-08-30perf event-parse: Use fixed size string for commsChris Phlipot1-4/+3
Some implementations of libc do not support the 'm' width modifier as part of the scanf string format specifier. This can cause the parsing to fail. Since the parser never checks if the scanf parsing was successesful, this can result in a crash. Change the comm string to be allocated as a fixed size instead of dynamically using 'm' scanf width modifier. This can be safely done since comm size is limited to 16 bytes by TASK_COMM_LEN within the kernel. This change prevents perf from crashing when linked against bionic as well as reduces the total number of heap allocations and frees invoked while accomplishing the same task. Signed-off-by: Chris Phlipot <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf util: Fix bad memory access in trace info.Chris Phlipot1-1/+1
In the write to the output_fd in the error condition of record_saved_cmdline(), we are writing 8 bytes from a memory location on the stack that contains a primitive that is only 4 bytes in size. Change the primitive to 8 bytes in size to match the size of the write in order to avoid reading unknown memory from the stack. Signed-off-by: Chris Phlipot <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf tools: Streamline bpf examples and headers installationArnaldo Carvalho de Melo1-8/+6
We were emitting 4 lines, two of them misleading: make: Entering directory '/home/acme/git/perf/tools/perf' <SNIP> INSTALL lib INSTALL include/bpf INSTALL lib INSTALL examples/bpf <SNIP> make: Leaving directory '/home/acme/git/perf/tools/perf' Make it more compact by showing just two lines: make: Entering directory '/home/acme/git/perf/tools/perf' INSTALL bpf-headers INSTALL bpf-examples make: Leaving directory '/home/acme/git/perf/tools/perf' Cc: Adrian Hunter <[email protected]> Cc: David Ahern <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Wang Nan <[email protected]> Link: https://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf evsel: Fix potential null pointer dereference in perf_evsel__new_idx()Hisao Tanabe1-2/+3
If evsel is NULL, we should return NULL to avoid a NULL pointer dereference a bit later in the code. Signed-off-by: Hisao Tanabe <[email protected]> Acked-by: Namhyung Kim <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Wang Nan <[email protected]> Fixes: 03e0a7df3efd ("perf tools: Introduce bpf-output event") LPU-Reference: [email protected] Link: https://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf arm64: Fix include path for asm-generic/unistd.hKim Phillips2-5/+6
The new syscall table support for arm64 mistakenly used the system's asm-generic/unistd.h file when processing the tools/arch/arm64/include/uapi/asm/unistd.h file's include directive: #include <asm-generic/unistd.h> See "Committer notes" section of commit 2b5882435606 "perf arm64: Generate system call table from asm/unistd.h" for more details. This patch removes the committer's temporary workaround, and instructs the host compiler to search the build tree's include path for the right copy of the unistd.h file, instead of the one on the system's /usr/include path. It thus fixes the committer's test that cross-builds an arm64 perf on an x86 platform running Ubuntu 14.04.5 LTS with an old toolchain: $ tools/perf/arch/arm64/entry/syscalls/mksyscalltbl /gcc-linaro-5.4.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-gcc gcc `pwd`/tools tools/arch/arm64/include/uapi/asm/unistd.h | grep bpf [280] = "bpf", Signed-off-by: Kim Phillips <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Hendrik Brueckner <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ravi Bangoria <[email protected]> Cc: Thomas Richter <[email protected]> Fixes: 2b5882435606 ("perf arm64: Generate system call table from asm/unistd.h") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpointJiri Olsa1-8/+3
We can safely enable the breakpoint back for both the fail and success paths by checking only the bp->attr.disabled, which either holds the new 'requested' disabled state or the original breakpoint state. Committer testing: At the end of the series, the 'perf test' entry introduced as the first patch now runs to completion without finding the fixed issues: # perf test "bp modify" 62: x86 bp modify : Ok # In verbose mode: # perf test -v "bp modify" 62: x86 bp modify : --- start --- test child forked, pid 5161 rip 5950a0, bp_1 0x5950a0 in bp_1 rip 5950a0, bp_1 0x5950a0 in bp_1 test child finished with 0 ---- end ---- x86 bp modify: Ok Suggested-by: Oleg Nesterov <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Signed-off-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: David Ahern <[email protected]> Cc: Milind Chabbi <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpointJiri Olsa1-4/+2
Currently we enable the breakpoint back only if the breakpoint modification was successful. If it fails we can leave the breakpoint in disabled state with attr->disabled == 0. We can safely enable the breakpoint back for both the fail and success paths by checking the bp->attr.disabled, which either holds the new 'requested' disabled state or the original breakpoint state. Suggested-by: Oleg Nesterov <[email protected]> Signed-off-by: Jiri Olsa <[email protected]> Acked-by: Frederic Weisbecker <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: David Ahern <[email protected]> Cc: Milind Chabbi <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0Jiri Olsa1-3/+2
Once the breakpoint was succesfully modified, the attr->disabled value is in bp->attr.disabled. So there's no reason to set it again, removing that. Signed-off-by: Jiri Olsa <[email protected]> Acked-by: Frederic Weisbecker <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: David Ahern <[email protected]> Cc: Milind Chabbi <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled setJiri Olsa1-4/+6
We need to change the breakpoint even if the attr with new fields has disabled set to true. Current code prevents following user code to change the breakpoint address: ptrace(PTRACE_POKEUSER, child, offsetof(struct user, u_debugreg[0]), addr_1) ptrace(PTRACE_POKEUSER, child, offsetof(struct user, u_debugreg[0]), addr_2) ptrace(PTRACE_POKEUSER, child, offsetof(struct user, u_debugreg[7]), dr7) The first PTRACE_POKEUSER creates the breakpoint with attr.disabled set to true: ptrace_set_breakpoint_addr(nr = 0) struct perf_event *bp = t->ptrace_bps[nr]; ptrace_register_breakpoint(..., disabled = true) ptrace_fill_bp_fields(..., disabled) register_user_hw_breakpoint So the second PTRACE_POKEUSER will be omitted: ptrace_set_breakpoint_addr(nr = 0) struct perf_event *bp = t->ptrace_bps[nr]; struct perf_event_attr attr = bp->attr; modify_user_hw_breakpoint(bp, &attr) if (!attr->disabled) modify_user_hw_breakpoint_check Reported-by: Milind Chabbi <[email protected]> Signed-off-by: Jiri Olsa <[email protected]> Acked-by: Frederic Weisbecker <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: David Ahern <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf tests: Add breakpoint modify testsJiri Olsa4-0/+221
Adding to tests that aims on kernel breakpoint modification bugs. First test creates HW breakpoint, tries to change it and checks it was properly changed. It aims on kernel issue that prevents HW breakpoint to be changed via ptrace interface. The first test forks, the child sets itself as ptrace tracee and waits in signal for parent to trace it, then it calls bp_1 and quits. The parent does following steps: - creates a new breakpoint (id 0) for bp_2 function - changes that breakpoint to bp_1 function - waits for the breakpoint to hit and checks it has proper rip of bp_1 function This test aims on an issue in kernel preventing to change disabled breakpoints Second test mimics the first one except for few steps in the parent: - creates a new breakpoint (id 0) for bp_1 function - changes that breakpoint to bogus (-1) address - waits for the breakpoint to hit and checks it has proper rip of bp_1 function This test aims on an issue in kernel disabling enabled breakpoint after unsuccesful change. Committer testing: # uname -a Linux jouet 4.18.0-rc8-00002-g1236568ee3cb #12 SMP Tue Aug 7 14:08:26 -03 2018 x86_64 x86_64 x86_64 GNU/Linux # perf test -v "bp modify" 62: x86 bp modify : --- start --- test child forked, pid 25671 in bp_1 tracee exited prematurely 2 FAILED arch/x86/tests/bp-modify.c:209 modify test 1 failed test child finished with -1 ---- end ---- x86 bp modify: FAILED! # Signed-off-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: David Ahern <[email protected]> Cc: Milind Chabbi <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30perf annotate: Properly interpret indirect callMartin Liška1-2/+8
The patch changes the parsing of: callq *0x8(%rbx) from: 0.26 │ → callq *8 to: 0.26 │ → callq *0x8(%rbx) in this case an address is followed by a register, thus one can't parse only the address. Committer testing: 1) run 'perf record sleep 10' 2) before applying the patch, run: perf annotate --stdio2 > /tmp/before 3) after applying the patch, run: perf annotate --stdio2 > /tmp/after 4) diff /tmp/before /tmp/after: --- /tmp/before 2018-08-28 11:16:03.238384143 -0300 +++ /tmp/after 2018-08-28 11:15:39.335341042 -0300 @@ -13274,7 +13274,7 @@ ↓ jle 128 hash_value = hash_table->hash_func (key); mov 0x8(%rsp),%rdi - 0.91 → callq *30 + 0.91 → callq *0x30(%r12) mov $0x2,%r8d cmp $0x2,%eax node_hash = hash_table->hashes[node_index]; @@ -13848,7 +13848,7 @@ mov %r14,%rdi sub %rbx,%r13 mov %r13,%rdx - → callq *38 + → callq *0x38(%r15) cmp %rax,%r13 1.91 ↓ je 240 1b4: mov $0xffffffff,%r13d @@ -14026,7 +14026,7 @@ mov %rcx,-0x500(%rbp) mov %r15,%rsi mov %r14,%rdi - → callq *38 + → callq *0x38(%rax) mov -0x500(%rbp),%rcx cmp %rax,%rcx ↓ jne 9b0 <SNIP tons of other such cases> Signed-off-by: Martin Liška <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Tested-by: Kim Phillips <[email protected]> Cc: Jiri Olsa <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2018-08-30Merge tag 'mtd/for-4.19-rc2' of git://git.infradead.org/linux-mtdLinus Torvalds2-2/+7
Pull mtd fixes from Boris Brezillon: "Raw NAND fixes: - denali: Fix a regression caused by the nand_scan() rework - docg4: Fix a build error when gcc decides to not iniline some functions (can be reproduced with gcc 4.1.2): * tag 'mtd/for-4.19-rc2' of git://git.infradead.org/linux-mtd: mtd: rawnand: denali: do not pass zero maxchips to nand_scan() mtd: rawnand: docg4: Remove wrong __init annotations
2018-08-30Merge tag 'mmc-v4.19-2' of ↵Linus Torvalds5-14/+25
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc Pull MMC fixes from Ulf Hansson: "MMC core: - Fix unsupported parallel dispatch of requests MMC host: - atmel-mci/android-goldfish: Fixup logic of sg_copy_{from,to}_buffer - renesas_sdhi_internal_dmac: Prevent IRQ-storm due of DMAC IRQs - renesas_sdhi_internal_dmac: Fixup bad register offset" * tag 'mmc-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: renesas_sdhi_internal_dmac: mask DMAC interrupts mmc: renesas_sdhi_internal_dmac: fix #define RST_RESERVED_BITS mmc: block: Fix unsupported parallel dispatch of requests mmc: android-goldfish: fix bad logic of sg_copy_{from,to}_buffer conversion mmc: atmel-mci: fix bad logic of sg_copy_{from,to}_buffer conversion
2018-08-30tools/kvm_stat: re-animate display of dead guestsStefan Raspl1-0/+10
When filtering by guest (interactive commands 'p'/'g'), and the respective guest was destroyed, detect when the guest is up again through the guest name if possible. I.e. when displaying events for a specific guest, it is not necessary anymore to restart kvm_stat in case the guest is restarted. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: indicate dead guests as suchStefan Raspl1-3/+9
For destroyed guests, kvm_stat essentially freezes with the last data displayed. This is acceptable for users, in case they want to inspect the final data. But it looks a bit irritating. Therefore, detect this situation and display a respective indicator in the header. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: handle guest removals more gracefullyStefan Raspl1-2/+9
When running with the DebugFS provider, removal of a guest can result in a negative CurAvg/s, which looks rather confusing. If so, suppress the body refresh and print a message instead. To reproduce, have at least one guest A completely booted. Then start another guest B (which generates a huge amount of events), then destroy B. On the next refresh, kvm_stat should display a whole lot of negative values in the CurAvg/s column. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: don't reset stats when setting PID filter for debugfsStefan Raspl1-1/+0
When setting a PID filter in debugfs, we unnecessarily reset the statistics, although there is no reason to do so. This behavior was merely introduced with commit 9f114a03c6854f "tools/kvm_stat: add interactive command 'r'", most likely to mimic the behavior of the tracepoints provider in this respect. However, there are plenty of differences between the two providers, so there is no reason not to take advantage of the possibility to filter by PID without resetting the statistics. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: fix updates for dead guestsStefan Raspl1-1/+10
With pid filtering active, when a guest is removed e.g. via virsh shutdown, successive updates produce garbage. Therefore, we add code to detect this case and prevent further body updates. Note that when displaying the help dialog via 'h' in this case, once we exit we're stuck with the 'Collecting data...' message till we remove the filter. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: fix handling of invalid paths in debugfs providerStefan Raspl1-0/+8
When filtering by guest, kvm_stat displays garbage when the guest is destroyed - see sample output below. We add code to remove the invalid paths from the providers, so at least no more garbage is displayed. Here's a sample output to illustrate: kvm statistics - pid 13986 (foo) Event Total %Total CurAvg/s diagnose_258 -2 0.0 0 deliver_program_interruption -3 0.0 0 diagnose_308 -4 0.0 0 halt_poll_invalid -91 0.0 -6 deliver_service_signal -244 0.0 -16 halt_successful_poll -250 0.1 -17 exit_pei -285 0.1 -19 exit_external_request -312 0.1 -21 diagnose_9c -328 0.1 -22 userspace_handled -713 0.1 -47 halt_attempted_poll -939 0.2 -62 deliver_emergency_signal -3126 0.6 -208 halt_wakeup -7199 1.5 -481 exit_wait_state -7379 1.5 -493 diagnose_500 -56499 11.5 -3757 exit_null -85491 17.4 -5685 diagnose_44 -133300 27.1 -8874 exit_instruction -195898 39.8 -13037 Total -492063 Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30tools/kvm_stat: fix python3 issuesStefan Raspl1-3/+3
Python3 returns a float for a regular division - switch to a division operator that returns an integer. Furthermore, filters return a generator object instead of the actual list - wrap result in yet another list, which makes it still work in both, Python2 and 3. Signed-off-by: Stefan Raspl <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30vfs: add the fadvise() file operationAmir Goldstein3-33/+53
This is going to be used by overlayfs and possibly useful for other filesystems. Signed-off-by: Amir Goldstein <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>
2018-08-30Documentation/filesystems: update documentation of file_operationsAmir Goldstein1-2/+16
...to kernel 4.18. Signed-off-by: Amir Goldstein <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>
2018-08-30ovl: fix GPF in swapfile_activate of file from overlayfs over xfsAmir Goldstein2-3/+6
Since overlayfs implements stacked file operations, the underlying filesystems are not supposed to be exposed to the overlayfs file, whose f_inode is an overlayfs inode. Assigning an overlayfs file to swap_file results in an attempt of xfs code to dereference an xfs_inode struct from an ovl_inode pointer: CPU: 0 PID: 2462 Comm: swapon Not tainted 4.18.0-xfstests-12721-g33e17876ea4e #3402 RIP: 0010:xfs_find_bdev_for_inode+0x23/0x2f Call Trace: xfs_iomap_swapfile_activate+0x1f/0x43 __se_sys_swapon+0xb1a/0xee9 Fix this by not assigning the real inode mapping to f_mapping, which will cause swapon() to return an error (-EINVAL). Although it makes sense not to allow setting swpafile on an overlayfs file, some users may depend on it, so we may need to fix this up in the future. Keeping f_mapping pointing to overlay inode mapping will cause O_DIRECT open to fail. Fix this by installing ovl_aops with noop_direct_IO in overlay inode mapping. Keeping f_mapping pointing to overlay inode mapping will cause other a_ops related operations to fail (e.g. readahead()). Those will be fixed by follow up patches. Suggested-by: Miklos Szeredi <[email protected]> Fixes: f7c72396d0de ("ovl: add O_DIRECT support") Signed-off-by: Amir Goldstein <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>
2018-08-30ovl: respect FIEMAP_FLAG_SYNC flagAmir Goldstein1-0/+4
Stacked overlayfs fiemap operation broke xfstests that test delayed allocation (with "_test_generic_punch -d"), because ovl_fiemap() failed to write dirty pages when requested. Fixes: 9e142c4102db ("ovl: add ovl_fiemap()") Signed-off-by: Amir Goldstein <[email protected]> Signed-off-by: Miklos Szeredi <[email protected]>
2018-08-30KVM: x86: Unexport x86_emulate_instruction()Sean Christopherson3-15/+18
Allowing x86_emulate_instruction() to be called directly has led to subtle bugs being introduced, e.g. not setting EMULTYPE_NO_REEXECUTE in the emulation type. While most of the blame lies on re-execute being opt-out, exporting x86_emulate_instruction() also exposes its cr2 parameter, which may have contributed to commit d391f1207067 ("x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested") using x86_emulate_instruction() instead of emulate_instruction() because "hey, I have a cr2!", which in turn introduced its EMULTYPE_NO_REEXECUTE bug. Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()Sean Christopherson4-17/+17
Lack of the kvm_ prefix gives the impression that it's a VMX or SVM specific function, and there's no conflict that prevents adding the kvm_ prefix. Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: Do not re-{try,execute} after failed emulation in L2Sean Christopherson2-2/+11
Commit a6f177efaa58 ("KVM: Reenter guest after emulation failure if due to access to non-mmio address") added reexecute_instruction() to handle the scenario where two (or more) vCPUS race to write a shadowed page, i.e. reexecute_instruction() is intended to return true if and only if the instruction being emulated was accessing a shadowed page. As L0 is only explicitly shadowing L1 tables, an emulation failure of a nested VM instruction cannot be due to a race to write a shadowed page and so should never be re-executed. This fixes an issue where an "MMIO" emulation failure[1] in L2 is all but guaranteed to result in an infinite loop when TDP is enabled. Because "cr2" is actually an L2 GPA when TDP is enabled, calling kvm_mmu_gva_to_gpa_write() to translate cr2 in the non-direct mapped case (L2 is never direct mapped) will almost always yield UNMAPPED_GVA and cause reexecute_instruction() to immediately return true. The !mmio_info_in_cache() check in kvm_mmu_page_fault() doesn't catch this case because mmio_info_in_cache() returns false for a nested MMU (the MMIO caching currently handles L1 only, e.g. to cache nested guests' GPAs we'd have to manually flush the cache when switching between VMs and when L1 updated its page tables controlling the nested guest). Way back when, commit 68be0803456b ("KVM: x86: never re-execute instruction with enabled tdp") changed reexecute_instruction() to always return false when using TDP under the assumption that KVM would only get into the emulator for MMIO. Commit 95b3cf69bdf8 ("KVM: x86: let reexecute_instruction work for tdp") effectively reverted that behavior in order to handle the scenario where emulation failed due to an access from L1 to the shadow page tables for L2, but it didn't account for the case where emulation failed in L2 with TDP enabled. All of the above logic also applies to retry_instruction(), added by commit 1cb3f3ae5a38 ("KVM: x86: retry non-page-table writing instructions"). An indefinite loop in retry_instruction() should be impossible as it protects against retrying the same instruction over and over, but it's still correct to not retry an L2 instruction in the first place. Fix the immediate issue by adding a check for a nested guest when determining whether or not to allow retry in kvm_mmu_page_fault(). In addition to fixing the immediate bug, add WARN_ON_ONCE in the retry functions since they are not designed to handle nested cases, i.e. they need to be modified even if there is some scenario in the future where we want to allow retrying a nested guest. [1] This issue was encountered after commit 3a2936dedd20 ("kvm: mmu: Don't expose private memslots to L2") changed the page fault path to return KVM_PFN_NOSLOT when translating an L2 access to a prive memslot. Returning KVM_PFN_NOSLOT is semantically correct when we want to hide a memslot from L2, i.e. there effectively is no defined memory region for L2, but it has the unfortunate side effect of making KVM think the GFN is a MMIO page, thus triggering emulation. The failure occurred with in-development code that deliberately exposed a private memslot to L2, which L2 accessed with an instruction that is not emulated by KVM. Fixes: 95b3cf69bdf8 ("KVM: x86: let reexecute_instruction work for tdp") Fixes: 1cb3f3ae5a38 ("KVM: x86: retry non-page-table writing instructions") Signed-off-by: Sean Christopherson <[email protected]> Cc: Jim Mattson <[email protected]> Cc: Krish Sadhukhan <[email protected]> Cc: Xiao Guangrong <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: Default to not allowing emulation retry in kvm_mmu_page_faultSean Christopherson1-6/+12
Effectively force kvm_mmu_page_fault() to opt-in to allowing retry to make it more obvious when and why it allows emulation to be retried. Previously this approach was less convenient due to retry and re-execute behavior being controlled by separate flags that were also inverted in their implementations (opt-in versus opt-out). Suggested-by: Paolo Bonzini <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: Merge EMULTYPE_RETRY and EMULTYPE_ALLOW_REEXECUTESean Christopherson3-7/+6
retry_instruction() and reexecute_instruction() are a package deal, i.e. there is no scenario where one is allowed and the other is not. Merge their controlling emulation type flags to enforce this in code. Name the combined flag EMULTYPE_ALLOW_RETRY to make it abundantly clear that we are allowing re{try,execute} to occur, as opposed to explicitly requesting retry of a previously failed instruction. Signed-off-by: Sean Christopherson <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: Invert emulation re-execute behavior to make it opt-inSean Christopherson3-7/+5
Re-execution of an instruction after emulation decode failure is intended to be used only when emulating shadow page accesses. Invert the flag to make allowing re-execution opt-in since that behavior is by far in the minority. Signed-off-by: Sean Christopherson <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: x86: SVM: Set EMULTYPE_NO_REEXECUTE for RSM emulationSean Christopherson2-2/+9
Re-execution after an emulation decode failure is only intended to handle a case where two or vCPUs race to write a shadowed page, i.e. we should never re-execute an instruction as part of RSM emulation. Add a new helper, kvm_emulate_instruction_from_buffer(), to support emulating from a pre-defined buffer. This eliminates the last direct call to x86_emulate_instruction() outside of kvm_mmu_page_fault(), which means x86_emulate_instruction() can be unexported in a future patch. Fixes: 7607b7174405 ("KVM: SVM: install RSM intercept") Cc: Brijesh Singh <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: VMX: Do not allow reexecute_instruction() when skipping MMIO instrSean Christopherson1-2/+2
Re-execution after an emulation decode failure is only intended to handle a case where two or vCPUs race to write a shadowed page, i.e. we should never re-execute an instruction as part of MMIO emulation. As handle_ept_misconfig() is only used for MMIO emulation, it should pass EMULTYPE_NO_REEXECUTE when using the emulator to skip an instr in the fast-MMIO case where VM_EXIT_INSTRUCTION_LEN is invalid. And because the cr2 value passed to x86_emulate_instruction() is only destined for use when retrying or reexecuting, we can simply call emulate_instruction(). Fixes: d391f1207067 ("x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested") Cc: Vitaly Kuznetsov <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Cc: [email protected] Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: SVM: remove unused variable dst_vaddr_endColin Ian King1-2/+1
Variable dst_vaddr_end is being assigned but is never used hence it is redundant and can be removed. Cleans up clang warning: variable 'dst_vaddr_end' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30KVM: nVMX: avoid redundant double assignment of nested_run_pendingVitaly Kuznetsov1-3/+0
nested_run_pending is set 20 lines above and check_vmentry_prereqs()/ check_vmentry_postreqs() don't seem to be resetting it (the later, however, checks it). Signed-off-by: Vitaly Kuznetsov <[email protected]> Reviewed-by: Paolo Bonzini <[email protected]> Reviewed-by: Jim Mattson <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Reviewed-by: Krish Sadhukhan <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>
2018-08-30ALSA: hda - Fix cancel_work_sync() stall from jackpoll workTakashi Iwai1-1/+2
On AMD/ATI controllers, the HD-audio controller driver allows a bus reset upon the error recovery, and its procedure includes the cancellation of pending jack polling work as found in snd_hda_bus_codec_reset(). This works usually fine, but it becomes a problem when the reset happens from the jack poll work itself; then calling cancel_work_sync() from the work being processed tries to wait the finish endlessly. As a workaround, this patch adds the check of current_work() and applies the cancel_work_sync() only when it's not from the jackpoll_work. This doesn't fix the root cause of the reported error below, but at least, it eases the unexpected stall of the whole system. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200937 Cc: <[email protected]> Cc: Lukas Wunner <[email protected]> Signed-off-by: Takashi Iwai <[email protected]>
2018-08-30arm/arm64: smccc-1.1: Handle function result as parametersMarc Zyngier1-10/+20
If someone has the silly idea to write something along those lines: extern u64 foo(void); void bar(struct arm_smccc_res *res) { arm_smccc_1_1_smc(0xbad, foo(), res); } they are in for a surprise, as this gets compiled as: 0000000000000588 <bar>: 588: a9be7bfd stp x29, x30, [sp, #-32]! 58c: 910003fd mov x29, sp 590: f9000bf3 str x19, [sp, #16] 594: aa0003f3 mov x19, x0 598: aa1e03e0 mov x0, x30 59c: 94000000 bl 0 <_mcount> 5a0: 94000000 bl 0 <foo> 5a4: aa0003e1 mov x1, x0 5a8: d4000003 smc #0x0 5ac: b4000073 cbz x19, 5b8 <bar+0x30> 5b0: a9000660 stp x0, x1, [x19] 5b4: a9010e62 stp x2, x3, [x19, #16] 5b8: f9400bf3 ldr x19, [sp, #16] 5bc: a8c27bfd ldp x29, x30, [sp], #32 5c0: d65f03c0 ret 5c4: d503201f nop The call to foo "overwrites" the x0 register for the return value, and we end up calling the wrong secure service. A solution is to evaluate all the parameters before assigning anything to specific registers, leading to the expected result: 0000000000000588 <bar>: 588: a9be7bfd stp x29, x30, [sp, #-32]! 58c: 910003fd mov x29, sp 590: f9000bf3 str x19, [sp, #16] 594: aa0003f3 mov x19, x0 598: aa1e03e0 mov x0, x30 59c: 94000000 bl 0 <_mcount> 5a0: 94000000 bl 0 <foo> 5a4: aa0003e1 mov x1, x0 5a8: d28175a0 mov x0, #0xbad 5ac: d4000003 smc #0x0 5b0: b4000073 cbz x19, 5bc <bar+0x34> 5b4: a9000660 stp x0, x1, [x19] 5b8: a9010e62 stp x2, x3, [x19, #16] 5bc: f9400bf3 ldr x19, [sp, #16] 5c0: a8c27bfd ldp x29, x30, [sp], #32 5c4: d65f03c0 ret Reported-by: Julien Grall <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Will Deacon <[email protected]>
2018-08-30scsi: qedi: Add the CRC size within iSCSI NVM imageNilesh Javali2-14/+21
The QED driver commit, 1ac4329a1cff ("qed: Add configuration information to register dump and debug data"), removes the CRC length validation causing nvm_get_image failure while loading qedi driver: [qed_mcp_get_nvm_image:2700(host_10-0)]Image [0] is too big - 00006008 bytes where only 00006004 are available [qedi_get_boot_info:2253]:10: Could not get NVM image. ret = -12 Hence add and adjust the CRC size to iSCSI NVM image to read boot info at qedi load time. Signed-off-by: Nilesh Javali <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>
2018-08-30scsi: iscsi: target: Fix conn_ops double freeMike Christie3-75/+77
If iscsi_login_init_conn fails it can free conn_ops. __iscsi_target_login_thread will then call iscsi_target_login_sess_out which will also free it. This fixes the problem by organizing conn allocation/setup into parts that are needed through the life of the conn and parts that are only needed for the login. The free functions then release what was allocated in the alloc functions. With this patch we have: iscsit_alloc_conn/iscsit_free_conn - allocs/frees the conn we need for the entire life of the conn. iscsi_login_init_conn/iscsi_target_nego_release - allocs/frees the parts of the conn that are only needed during login. Signed-off-by: Mike Christie <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>
2018-08-30scsi: iscsi: target: Set conn->sess to NULL when iscsi_login_set_conn_values ↵Vincent Pelletier1-5/+3
fails Fixes a use-after-free reported by KASAN when later iscsi_target_login_sess_out gets called and it tries to access conn->sess->se_sess: Disabling lock debugging due to kernel taint iSCSI Login timeout on Network Portal [::]:3260 iSCSI Login negotiation failed. ================================================================== BUG: KASAN: use-after-free in iscsi_target_login_sess_out.cold.12+0x58/0xff [iscsi_target_mod] Read of size 8 at addr ffff880109d070c8 by task iscsi_np/980 CPU: 1 PID: 980 Comm: iscsi_np Tainted: G O 4.17.8kasan.sess.connops+ #4 Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 05/19/2014 Call Trace: dump_stack+0x71/0xac print_address_description+0x65/0x22e ? iscsi_target_login_sess_out.cold.12+0x58/0xff [iscsi_target_mod] kasan_report.cold.6+0x241/0x2fd iscsi_target_login_sess_out.cold.12+0x58/0xff [iscsi_target_mod] iscsi_target_login_thread+0x1086/0x1710 [iscsi_target_mod] ? __sched_text_start+0x8/0x8 ? iscsi_target_login_sess_out+0x250/0x250 [iscsi_target_mod] ? __kthread_parkme+0xcc/0x100 ? parse_args.cold.14+0xd3/0xd3 ? iscsi_target_login_sess_out+0x250/0x250 [iscsi_target_mod] kthread+0x1a0/0x1c0 ? kthread_bind+0x30/0x30 ret_from_fork+0x35/0x40 Allocated by task 980: kasan_kmalloc+0xbf/0xe0 kmem_cache_alloc_trace+0x112/0x210 iscsi_target_login_thread+0x816/0x1710 [iscsi_target_mod] kthread+0x1a0/0x1c0 ret_from_fork+0x35/0x40 Freed by task 980: __kasan_slab_free+0x125/0x170 kfree+0x90/0x1d0 iscsi_target_login_thread+0x1577/0x1710 [iscsi_target_mod] kthread+0x1a0/0x1c0 ret_from_fork+0x35/0x40 The buggy address belongs to the object at ffff880109d06f00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 456 bytes inside of 512-byte region [ffff880109d06f00, ffff880109d07100) The buggy address belongs to the page: page:ffffea0004274180 count:1 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0 flags: 0x17fffc000008100(slab|head) raw: 017fffc000008100 0000000000000000 0000000000000000 00000001000c000c raw: dead000000000100 dead000000000200 ffff88011b002e00 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880109d06f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff880109d07000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff880109d07080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff880109d07100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff880109d07180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== Signed-off-by: Vincent Pelletier <[email protected]> [rebased against idr/ida changes and to handle ret review comments from Matthew] Signed-off-by: Mike Christie <[email protected]> Cc: Matthew Wilcox <[email protected]> Reviewed-by: Matthew Wilcox <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>
2018-08-30x86/asm: Use CC_SET()/CC_OUT() in __gen_sigismember()Uros Bizjak1-3/+4
Replace open-coded set instructions with CC_SET()/CC_OUT(). Signed-off-by: Uros Bizjak <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-08-30x86/alternatives: Lockdep-enforce text_mutex in text_poke*()Jiri Kosina1-4/+5
text_poke() and text_poke_bp() must be called with text_mutex held. Put proper lockdep anotation in place instead of just mentioning the requirement in a comment. Reported-by: Peter Zijlstra <[email protected]> Signed-off-by: Jiri Kosina <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Masami Hiramatsu <[email protected]> Cc: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-08-30objtool: Remove workaround for unreachable warnings from old GCCMasahiro Yamada1-2/+0
Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6") bumped the minimum GCC version to 4.6 for all architectures. This effectively reverts commit da541b20021c ("objtool: Skip unreachable warnings for GCC 4.4 and older"), which was a workaround for GCC 4.4 or older. Signed-off-by: Masahiro Yamada <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Josh Poimboeuf <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Michal Marek <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2018-08-30notifier: Remove notifier header file wherever not usedMukesh Ojha7-7/+0
The conversion of the hotplug notifiers to a state machine left the notifier.h includes around in some places. Remove them. Signed-off-by: Mukesh Ojha <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-08-30watchdog: Mark watchdog touch functions as notraceVincent Whitchurch3-4/+4
Some architectures need to use stop_machine() to patch functions for ftrace, and the assumption is that the stopped CPUs do not make function calls to traceable functions when they are in the stopped state. Commit ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE") added calls to the watchdog touch functions from the stopped CPUs and those functions lack notrace annotations. This leads to crashes when enabling/disabling ftrace on ARM kernels built with the Thumb-2 instruction set. Fix it by adding the necessary notrace annotations. Fixes: ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE") Signed-off-by: Vincent Whitchurch <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2018-08-30x86/entry/64: Wipe KASAN stack shadow before rewind_stack_do_exit()Jann Horn1-0/+4
Reset the KASAN shadow state of the task stack before rewinding RSP. Without this, a kernel oops will leave parts of the stack poisoned, and code running under do_exit() can trip over such poisoned regions and cause nonsensical false-positive KASAN reports about stack-out-of-bounds bugs. This does not wipe the exception stacks; if an oops happens on an exception stack, it might result in random KASAN false-positives from other tasks afterwards. This is probably relatively uninteresting, since if the kernel oopses on an exception stack, there are most likely bigger things to worry about. It'd be more interesting if vmapped stacks and KASAN were compatible, since then handle_stack_overflow() would oops from exception stack context. Fixes: 2deb4be28077 ("x86/dumpstack: When OOPSing, rewind the stack before do_exit()") Signed-off-by: Jann Horn <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Andrey Ryabinin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Kees Cook <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2018-08-30x86/irqflags: Mark native_restore_fl extern inlineNick Desaulniers1-1/+2
This should have been marked extern inline in order to pick up the out of line definition in arch/x86/kernel/irqflags.S. Fixes: 208cbb325589 ("x86/irqflags: Provide a declaration for native_save_fl") Reported-by: Ben Hutchings <[email protected]> Signed-off-by: Nick Desaulniers <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Juergen Gross <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2018-08-30x86/build: Remove jump label quirk for GCC older than 4.5.2Masahiro Yamada2-16/+0
Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6") bumped the minimum GCC version to 4.6 for all architectures. Remove the workaround code. It was the only user of cc-if-fullversion. Remove the macro as well. Signed-off-by: Masahiro Yamada <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Michal Marek <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2018-08-30mac80211: always account for A-MSDU header changesJohannes Berg1-5/+7
In the error path of changing the SKB headroom of the second A-MSDU subframe, we would not account for the already-changed length of the first frame that just got converted to be in A-MSDU format and thus is a bit longer now. Fix this by doing the necessary accounting. It would be possible to reorder the operations, but that would make the code more complex (to calculate the necessary pad), and the headroom expansion should not fail frequently enough to make that worthwhile. Fixes: 6e0456b54545 ("mac80211: add A-MSDU tx support") Signed-off-by: Johannes Berg <[email protected]> Acked-by: Lorenzo Bianconi <[email protected]> Signed-off-by: Johannes Berg <[email protected]>