- 21 Dec, 2021 1 commit
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Eric W. Biederman authored
Failed allocates are not expected when setting up the initial task and it is not really possible to handle them either. So I added a warning to report if such an allocation failure ever happens. Correct the sense of the warning so it warns when an allocation failure happens not when the allocation succeeded. Oops. Reported-by:
kernel test robot <oliver.sang@intel.com> Reported-by:
Stephen Rothwell <sfr@canb.auug.org.au> Reported-by:
Naresh Kamboju <naresh.kamboju@linaro.org> Link: https://lkml.kernel.org/r/20211221231611.785b74cf@canb.auug.org.au Link: https://lkml.kernel.org/r/CA+G9fYvLaR5CF777CKeWTO+qJFTN6vAvm95gtzN+7fw3Wi5hkA@mail.gmail.com Link: https://lkml.kernel.org/r/20211216102956.GC10708@xsang-OptiPlex-9020 Fixes: 40966e31 ("kthread: Ensure struct kthread is present for all kthreads") Signed-off-by:
"Eric W. Biederman" <ebiederm@xmission.com>
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- 20 Dec, 2021 2 commits
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Eric W. Biederman authored
I just fixed a bug in copy_process when using the label bad_fork_cleanup_threadgroup_lock. While fixing the bug I looked closer at the label and realized it has been misnamed since 568ac888 ("cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork"). Fix the name so that fork is easier to understand. Signed-off-by:
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Eric W. Biederman authored
Mark Brown <broonie@kernel.org> reported: > This is also causing further build errors including but not limited to: > > /tmp/next/build/kernel/fork.c: In function 'copy_process': > /tmp/next/build/kernel/fork.c:2106:4: error: label 'bad_fork_cleanup_threadgroup_lock' used but not defined > 2106 | goto bad_fork_cleanup_threadgroup_lock; > | ^~~~ It turns out that I messed up and was depending upon a label protected by an ifdef. Move the label out of the ifdef as the ifdef around the label no longer makes sense (if it ever did). Link: https://lkml.kernel.org/r/YbugCP144uxXvRsk@sirena.org.uk Fixes: 40966e31 ("kthread: Ensure struct kthread is present for all kthreads") Signed-off-by:
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- 15 Dec, 2021 1 commit
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Eric W. Biederman authored
Recently the kbuild robot reported two new errors: >> lib/kunit/kunit-example-test.o: warning: objtool: .text.unlikely: unexpected end of section >> arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes() I don't know why they did not occur in my test setup but after digging it I realized I had accidentally dropped a comma in tools/objtool/check.c when I renamed rewind_stack_do_exit to rewind_stack_and_make_dead. Add that comma back to fix objtool errors. Link: https://lkml.kernel.org/r/202112140949.Uq5sFKR1-lkp@intel.com Fixes: 0e25498f ("exit: Add and use make_task_dead.") Reported-by:
kernel test robot <lkp@intel.com> Signed-off-by:
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- 14 Dec, 2021 1 commit
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Eric W. Biederman authored
I misspelled kthread_complete_and_exit in the kernel doc comment fix it. Link: https://lkml.kernel.org/r/202112141329.KBkyJ5ql-lkp@intel.com Link: https://lkml.kernel.org/r/202112141422.Cykr6YUS-lkp@intel.comReported-by:
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- 13 Dec, 2021 10 commits
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Eric W. Biederman authored
The exit code of kernel threads has different semantics than the exit_code of userspace tasks. To avoid confusion and allow the userspace implementation to change as needed move the kernel thread exit code into struct kthread. Signed-off-by: -
Eric W. Biederman authored
Today the rules are a bit iffy and arbitrary about which kernel threads have struct kthread present. Both idle threads and thread started with create_kthread want struct kthread present so that is effectively all kernel threads. Make the rule that if PF_KTHREAD and the task is running then struct kthread is present. This will allow the kernel thread code to using tsk->exit_code with different semantics from ordinary processes. To make ensure that struct kthread is present for all kernel threads move it's allocation into copy_process. Add a deallocation of struct kthread in exec for processes that were kernel threads. Move the allocation of struct kthread for the initial thread earlier so that it is not repeated for each additional idle thread. Move the initialization of struct kthread into set_kthread_struct so that the structure is always and reliably initailized. Clear set_child_tid in free_kthread_struct to ensure the kthread struct is reliably freed during exec. The function free_kthread_struct does not need to clear vfork_done during exec as exec_mm_release called from exec_mmap has already cleared vfork_done. Signed-off-by: -
Eric W. Biederman authored
Update complete_and_exit to call kthread_exit instead of do_exit. Change the name to reflect this change in functionality. All of the users of complete_and_exit are causing the current kthread to exit so this change makes it clear what is happening. Move the implementation of kthread_complete_and_exit from kernel/exit.c to to kernel/kthread.c. As this function is kthread specific it makes most sense to live with the kthread functions. There are no functional change. Signed-off-by: -
Eric W. Biederman authored
Update module_put_and_exit to call kthread_exit instead of do_exit. Change the name to reflect this change in functionality. All of the users of module_put_and_exit are causing the current kthread to exit so this change makes it clear what is happening. There is no functional change. Signed-off-by: -
Eric W. Biederman authored
The way the per task_struct exit_code is used by kernel threads is not quite compatible how it is used by userspace applications. The low byte of the userspace exit_code value encodes the exit signal. While kthreads just use the value as an int holding ordinary kernel function exit status like -EPERM. Add kthread_exit to clearly separate the two kinds of uses. Signed-off-by: -
Eric W. Biederman authored
Now that there are no more modular uses of do_exit remove the EXPORT_SYMBOL. Suggested-by:
Christoph Hellwig <hch@infradead.org> Signed-off-by:
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Eric W. Biederman authored
When the kernel detects it is oops or otherwise force killing a task while it exits the code poorly attempts to permanently stop the task from scheduling. I say poorly because it is possible for a task in TASK_UINTERRUPTIBLE to be woken up. As it makes no sense for the task to continue call do_task_dead instead which actually does the work and permanently removes the task from the scheduler. Guaranteeing the task will never be woken up again. Signed-off-by: -
Eric W. Biederman authored
The beginning of do_exit has become cluttered and difficult to read as it is filled with checks to handle things that can only happen when the kernel is operating improperly. Now that we have a dedicated function for cleaning up a task when the kernel is operating improperly move the checks there. Signed-off-by: -
Eric W. Biederman authored
There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: -
Eric W. Biederman authored
My s390 assembly is not particularly good so I have read the history of the reference to do_exit copy_thread and have been able to verify that do_exit is not used. The general argument is that s390 has been changed to use the generic kernel_thread and kernel_execve and the generic versions do not call do_exit. So it is strange to see a do_exit reference sitting there. The history of the do_exit reference in s390's version of copy_thread seems conclusive that the do_exit reference is something that lingers and should have been removed several years ago. Up through 8d19f15a ("[PATCH] s390 update (1/27): arch.") the s390 code made a call to the exit(2) system call when a kernel thread finished. Then kernel_thread_starter was added which branched directly to the value in register 11 when the kernel thread finshed. The value in register 11 was set in kernel_thread to "regs.gprs[11] = (unsigned long) do_exit" In commit 37fe5d41 ("s390: fold kernel_thread_helper() into ret_from_fork()") kernel_thread_starter was moved into entry.S and entry64.S unchanged (except for the syntax differences between inline assemly and in the assembly file). In commit f9a7e025 ("s390: switch to generic kernel_thread()") the assignment to "gprs[11]" was moved into copy_thread from the old kernel_thread. The helper kernel_thread_starter was still being used and was still branching to "%r11" at the end. In commit 30dcb099 ("s390: switch to saner kernel_execve() semantics") kernel_thread_starter was changed to unconditionally branch to sysc_tracenogo instead to %r11 which held the value of do_exit. Unfortunately copy_thread was not updated to stop passing do_exit in "gprs[11]". In commit 56e62a73 ("s390: convert to generic entry") kernel_thread_starter was replaced by __ret_from_fork. And the code still continued to pass do_exit in "gprs[11]" despite __ret_from_fork not caring in the slightest. Remove this dead reference to do_exit to make it clear that s390 is not doing anything with do_exit in copy_thread. Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Fixes: 30dcb099 ("s390: switch to saner kernel_execve() semantics") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitAcked-by:
Heiko Carstens <hca@linux.ibm.com> Signed-off-by:
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- 03 Dec, 2021 1 commit
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Eric W. Biederman authored
I completed the first batch of signal changes for v5.17 against v5.16-rc1 before the SA_IMMUTABLE fixes where completed. Which leaves me with two lines of development that I want on my signal development branch both rooted at v5.16-rc1. Especially as I am hoping to reach the point of being able to remove SA_IMMUTABLE. Linus merged my SA_IMUTABLE fixes as: 7af959b5 ("Merge branch 'SA_IMMUTABLE-fixes-for-v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace") To avoid rebasing the development changes that are currently complete I am merging the work I sent upstream to Linus to make my life simpler. The SA_IMMUTABLE changes as they are described in Linus's merge commit. Pull exit-vs-signal handling fixes from Eric Biederman: "This is a small set of changes where debuggers were no longer able to intercept synchronous SIGTRAP and SIGSEGV, introduced by the exit cleanups. This is essentially the change you suggested with all of i's dotted and the t's crossed so that ptrace can intercept all of the cases it has been able to intercept the past, and all of the cases that made it to exit without giving ptrace a chance still don't give ptrace a chance" * 'SA_IMMUTABLE-fixes-for-v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: signal: Replace force_fatal_sig with force_exit_sig when in doubt signal: Don't always set SA_IMMUTABLE for forced signals Signed-off-by:
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- 19 Nov, 2021 2 commits
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Eric W. Biederman authored
Recently to prevent issues with SECCOMP_RET_KILL and similar signals being changed before they are delivered SA_IMMUTABLE was added. Unfortunately this broke debuggers[1][2] which reasonably expect to be able to trap synchronous SIGTRAP and SIGSEGV even when the target process is not configured to handle those signals. Add force_exit_sig and use it instead of force_fatal_sig where historically the code has directly called do_exit. This has the implementation benefits of going through the signal exit path (including generating core dumps) without the danger of allowing userspace to ignore or change these signals. This avoids userspace regressions as older kernels exited with do_exit which debuggers also can not intercept. In the future is should be possible to improve the quality of implementation of the kernel by changing some of these force_exit_sig calls to force_fatal_sig. That can be done where it matters on a case-by-case basis with careful analysis. Reported-by:
Kyle Huey <me@kylehuey.com> Reported-by:
Kees Cook <keescook@chromium.org> Tested-by:
Kyle Huey <khuey@kylehuey.com> Signed-off-by:
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Eric W. Biederman authored
Recently to prevent issues with SECCOMP_RET_KILL and similar signals being changed before they are delivered SA_IMMUTABLE was added. Unfortunately this broke debuggers[1][2] which reasonably expect to be able to trap synchronous SIGTRAP and SIGSEGV even when the target process is not configured to handle those signals. Update force_sig_to_task to support both the case when we can allow the debugger to intercept and possibly ignore the signal and the case when it is not safe to let userspace know about the signal until the process has exited. Suggested-by:
Linus Torvalds <torvalds@linux-foundation.org> Reported-by:
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- 17 Nov, 2021 4 commits
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Eric W. Biederman authored
Kyle Huey recently reported[1] that rr gets confused if SIGKILL prevents ptrace_signal from delivering a signal, as the kernel setups up a signal frame for a signal that rr did not have a chance to observe with ptrace. In looking into it I found a couple of bugs and a quality of implementation issue. - The test for signal_group_exit should be inside the for loop in get_signal. - Signals should be requeued on the same queue they were dequeued from. - When a fatal signal is pending ptrace_signal should not return another signal for delivery. Kyle Huey has verified[2] an earlier version of this change. I have reworked things one more time to completely fix the issues raised, and to keep the code maintainable long term. I have smoke tested this code and combined with a careful review I expect this code to work fine. Kyle if you can double check that my last round of changes still works for rr I would appreciate it. Eric W. Biederman (3): signal: In get_signal test for signal_group_exit every time through the loop signal: Requeue signals in the appropriate queue signal: Requeue ptrace signals fs/signalfd.c | 5 +++-- include/linux/sched/signal.h | 7 ++++--- kernel/signal.c | 44 ++++++++++++++++++++++++++------------------ 3 files changed, 33 insertions(+), 23 deletions(-) [1] https://lkml.kernel.org/r/20211101034147.6203-1-khuey@kylehuey.com [2] https://lkml.kernel.org/r/CAP045ApAX725ZfujaK-jJNkfCo5s+oVFpBvNfPJk+DKY8K7d=Q@mail.gmail.comTested-by: -
Eric W. Biederman authored
Kyle Huey <me@kylehuey.com> writes: > rr, a userspace record and replay debugger[0], uses the recorded register > state at PTRACE_EVENT_EXIT to find the point in time at which to cease > executing the program during replay. > > If a SIGKILL races with processing another signal in get_signal, it is > possible for the kernel to decline to notify the tracer of the original > signal. But if the original signal had a handler, the kernel proceeds > with setting up a signal handler frame as if the tracer had chosen to > deliver the signal unmodified to the tracee. When the kernel goes to > execute the signal handler that it has now modified the stack and registers > for, it will discover the pending SIGKILL, and terminate the tracee > without executing the handler. When PTRACE_EVENT_EXIT is delivered to > the tracer, however, the effects of handler setup will be visible to > the tracer. > > Because rr (the tracer) was never notified of the signal, it is not aware > that a signal handler frame was set up and expects the state of the program > at PTRACE_EVENT_EXIT to be a state that will be reconstructed naturally > by allowing the program to execute from the last event. When that fails > to happen during replay, rr will assert and die. > > The following patches add an explicit check for a newly pending SIGKILL > after the ptracer has been notified and the siglock has been reacquired. > If this happens, we stop processing the current signal and proceed > immediately to handling the SIGKILL. This makes the state reported at > PTRACE_EVENT_EXIT the unmodified state of the program, and also avoids the > work to set up a signal handler frame that will never be used. > > [0] https://rr-project.org/ The problem is that while the traced process makes it into ptrace_stop, the tracee is killed before the tracer manages to wait for the tracee and discover which signal was about to be delivered. More generally the problem is that while siglock was dropped a signal with process wide effect is short cirucit delivered to the entire process killing it, but the process continues to try and deliver another signal. In general it impossible to avoid all cases where work is performed after the process has been killed. In particular if the process is killed after get_signal returns the code will simply not know it has been killed until after delivering the signal frame to userspace. On the other hand when the code has already discovered the process has been killed and taken user space visible action that shows the kernel knows the process has been killed, it is just silly to then write the signal frame to the user space stack. Instead of being silly detect the process has been killed in ptrace_signal and requeue the signal so the code can pretend it was simply never dequeued for delivery. To test the process has been killed I use fatal_signal_pending rather than signal_group_exit to match the test in signal_pending_state which is used in schedule which is where ptrace_stop detects the process has been killed. Requeuing the signal so the code can pretend it was simply never dequeued improves the user space visible behavior that has been present since ebf5ebe3 ("[PATCH] signal-fixes-2.5.59-A4"). Kyle Huey verified that this change in behavior and makes rr happy. Reported-by:
Marko Mäkelä <marko.makela@mariadb.com> History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.giReviewed-by:
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Eric W. Biederman authored
In the event that a tracer changes which signal needs to be delivered and that signal is currently blocked then the signal needs to be requeued for later delivery. With the advent of CLONE_THREAD the kernel has 2 signal queues per task. The per process queue and the per task queue. Update the code so that if the signal is removed from the per process queue it is requeued on the per process queue. This is necessary to make it appear the signal was never dequeued. The rr debugger reasonably believes that the state of the process from the last ptrace_stop it observed until PTRACE_EVENT_EXIT can be recreated by simply letting a process run. If a SIGKILL interrupts a ptrace_stop this is not true today. So return signals to their original queue in ptrace_signal so that signals that are not delivered appear like they were never dequeued. Fixes: 794aa320 ("[PATCH] sigfix-2.5.40-D6") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.giReviewed-by:
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Eric W. Biederman authored
Recently while investigating a problem with rr and signals I noticed that siglock is dropped in ptrace_signal and get_signal does not jump to relock. Looking farther to see if the problem is anywhere else I see that do_signal_stop also returns if signal_group_exit is true. I believe that test can now never be true, but it is a bit hard to trace through and be certain. Testing signal_group_exit is not expensive, so move the test for signal_group_exit into the for loop inside of get_signal to ensure the test is never skipped improperly. This has been a potential problem since I added the test for signal_group_exit was added. Fixes: 35634ffa ("signal: Always notice exiting tasks") Reviewed-by:
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- 14 Nov, 2021 15 commits
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Linus Torvalds authored
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Gustavo A. R. Silva authored
Add Kconfig support for -Wimplicit-fallthrough for both GCC and Clang. The compiler option is under configuration CC_IMPLICIT_FALLTHROUGH, which is enabled by default. Special thanks to Nathan Chancellor who fixed the Clang bug[1][2]. This bugfix only appears in Clang 14.0.0, so older versions still contain the bug and -Wimplicit-fallthrough won't be enabled for them, for now. This concludes a long journey and now we are finally getting rid of the unintentional fallthrough bug-class in the kernel, entirely. :) Link: https://github.com/llvm/llvm-project/commit/9ed4a94d6451046a51ef393cd62f00710820a7e8 [1] Link: https://bugs.llvm.org/show_bug.cgi?id=51094 [2] Link: https://github.com/KSPP/linux/issues/115 Link: https://github.com/ClangBuiltLinux/linux/issues/236Co-developed-by:
Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by:
Nathan Chancellor <nathan@kernel.org> Tested-by:
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git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds authored
Pull xfs cleanups from Darrick Wong: "The most 'exciting' aspect of this branch is that the xfsprogs maintainer and I have worked through the last of the code discrepancies between kernel and userspace libxfs such that there are no code differences between the two except for #includes. IOWs, diff suffices to demonstrate that the userspace tools behave the same as the kernel, and kernel-only bits are clearly marked in the /kernel/ source code instead of just the userspace source. Summary: - Clean up open-coded swap() calls. - A little bit of #ifdef golf to complete the reunification of the kernel and userspace libxfs source code" * tag 'xfs-5.16-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: sync xfs_btree_split macros with userspace libxfs xfs: #ifdef out perag code for userspace xfs: use swap() to make dabtree code cleaner -
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linuxLinus Torvalds authored
Pull more parisc fixes from Helge Deller: "Fix a build error in stracktrace.c, fix resolving of addresses to function names in backtraces, fix single-stepping in assembly code and flush userspace pte's when using set_pte_at()" * tag 'for-5.16/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc/entry: fix trace test in syscall exit path parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page parisc: Fix implicit declaration of function '__kernel_text_address' parisc: Fix backtrace to always include init funtion names
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git://git.libc.org/linux-shLinus Torvalds authored
Pull arch/sh updates from Rich Felker. * tag 'sh-for-5.16' of git://git.libc.org/linux-sh: sh: pgtable-3level: Fix cast to pointer from integer of different size sh: fix READ/WRITE redefinition warnings sh: define __BIG_ENDIAN for math-emu sh: math-emu: drop unused functions sh: fix kconfig unmet dependency warning for FRAME_POINTER sh: Cleanup about SPARSE_IRQ sh: kdump: add some attribute to function maple: fix wrong return value of maple_bus_init(). sh: boot: avoid unneeded rebuilds under arch/sh/boot/compressed/ sh: boot: add intermediate vmlinux.bin* to targets instead of extra-y sh: boards: Fix the cacography in irq.c sh: check return code of request_irq sh: fix trivial misannotations
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git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds authored
Pull ARM fixes from Russell King: - Fix early_iounmap - Drop cc-option fallbacks for architecture selection * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9156/1: drop cc-option fallbacks for architecture selection ARM: 9155/1: fix early early_iounmap()
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git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds authored
Pull devicetree fixes from Rob Herring: - Two fixes due to DT node name changes on Arm, Ltd. boards - Treewide rename of Ingenic CGU headers - Update ST email addresses - Remove Netlogic DT bindings - Dropping few more cases of redundant 'maxItems' in schemas - Convert toshiba,tc358767 bridge binding to schema * tag 'devicetree-fixes-for-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: dt-bindings: watchdog: sunxi: fix error in schema bindings: media: venus: Drop redundant maxItems for power-domain-names dt-bindings: Remove Netlogic bindings clk: versatile: clk-icst: Ensure clock names are unique of: Support using 'mask' in making device bus id dt-bindings: treewide: Update @st.com email address to @foss.st.com dt-bindings: media: Update maintainers for st,stm32-hwspinlock.yaml dt-bindings: media: Update maintainers for st,stm32-cec.yaml dt-bindings: mfd: timers: Update maintainers for st,stm32-timers dt-bindings: timer: Update maintainers for st,stm32-timer dt-bindings: i2c: imx: hardware do not restrict clock-frequency to only 100 and 400 kHz dt-bindings: display: bridge: Convert toshiba,tc358767.txt to yaml dt-bindings: Rename Ingenic CGU headers to ingenic,*.h
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Thomas Gleixner: "A single fix for POSIX CPU timers to address a problem where POSIX CPU timer delivery stops working for a new child task because copy_process() copies state information which is only valid for the parent task" * tag 'timers-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull irq fixes from Thomas Gleixner: "A set of fixes for the interrupt subsystem Core code: - A regression fix for the Open Firmware interrupt mapping code where a interrupt controller property in a node caused a map property in the same node to be ignored. Interrupt chip drivers: - Workaround a limitation in SiFive PLIC interrupt chip which silently ignores an EOI when the interrupt line is masked. - Provide the missing mask/unmask implementation for the CSKY MP interrupt controller. PCI/MSI: - Prevent a use after free when PCI/MSI interrupts are released by destroying the sysfs entries before freeing the memory which is accessed in the sysfs show() function. - Implement a mask quirk for the Nvidia ION AHCI chip which does not advertise masking capability despite implementing it. Even worse the chip comes out of reset with all MSI entries masked, which due to the missing masking capability never get unmasked. - Move the check which prevents accessing the MSI[X] masking for XEN back into the low level accessors. The recent consolidation missed that these accessors can be invoked from places which do not have that check which broke XEN. Move them back to he original place instead of sprinkling tons of these checks all over the code" * tag 'irq-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: of/irq: Don't ignore interrupt-controller when interrupt-map failed irqchip/sifive-plic: Fixup EOI failed when masked irqchip/csky-mpintc: Fixup mask/unmask implementation PCI/MSI: Destroy sysfs before freeing entries PCI: Add MSI masking quirk for Nvidia ION AHCI PCI/MSI: Deal with devices lying about their MSI mask capability PCI/MSI: Move non-mask check back into low level accessors -
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 static call update from Thomas Gleixner: "A single fix for static calls to make the trampoline patching more robust by placing explicit signature bytes after the call trampoline to prevent patching random other jumps like the CFI jump table entries" * tag 'locking-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: static_call,x86: Robustify trampoline patching
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull scheduler fixes from Borislav Petkov: - Avoid touching ~100 config files in order to be able to select the preemption model - clear cluster CPU masks too, on the CPU unplug path - prevent use-after-free in cfs - Prevent a race condition when updating CPU cache domains - Factor out common shared part of smp_prepare_cpus() into a common helper which can be called by both baremetal and Xen, in order to fix a booting of Xen PV guests * tag 'sched_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: preempt: Restore preemption model selection configs arch_topology: Fix missing clear cluster_cpumask in remove_cpu_topology() sched/fair: Prevent dead task groups from regaining cfs_rq's sched/core: Mitigate race cpus_share_cache()/update_top_cache_domain() x86/smp: Factor out parts of native_smp_prepare_cpus()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf fixes from Borislav Petkov: - Prevent unintentional page sharing by checking whether a page reference to a PMU samples page has been acquired properly before that - Make sure the LBR_SELECT MSR is saved/restored too - Reset the LBR_SELECT MSR when resetting the LBR PMU to clear any residual data left * tag 'perf_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Avoid put_page() when GUP fails perf/x86/vlbr: Add c->flags to vlbr event constraints perf/x86/lbr: Reset LBR_SELECT during vlbr reset
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Borislav Petkov: - Add the model number of a new, Raptor Lake CPU, to intel-family.h - Do not log spurious corrected MCEs on SKL too, due to an erratum - Clarify the path of paravirt ops patches upstream - Add an optimization to avoid writing out AMX components to sigframes when former are in init state * tag 'x86_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Add Raptor Lake to Intel family x86/mce: Add errata workaround for Skylake SKX37 MAINTAINERS: Add some information to PARAVIRT_OPS entry x86/fpu: Optimize out sigframe xfeatures when in init state
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Linus Torvalds authored
Merge tag 'perf-tools-for-v5.16-2021-11-13' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull more perf tools updates from Arnaldo Carvalho de Melo: "Hardware tracing: - ARM: * Print the size of the buffer size consistently in hexadecimal in ARM Coresight. * Add Coresight snapshot mode support. * Update --switch-events docs in 'perf record'. * Support hardware-based PID tracing. * Track task context switch for cpu-mode events. - Vendor events: * Add metric events JSON file for power10 platform perf test: - Get 'perf test' unit tests closer to kunit. - Topology tests improvements. - Remove bashisms from some tests. perf bench: - Fix memory leak of perf_cpu_map__new() in the futex benchmarks. libbpf: - Add some more weak libbpf functions o allow building with the libbpf versions, old ones, present in distros. libbeauty: - Translate [gs]setsockopt 'level' argument integer values to strings. tools headers UAPI: - Sync futex_waitv, arch prctl, sound, i195_drm and msr-index files with the kernel sources. Documentation: - Add documentation to 'struct symbol'. - Synchronize the definition of enum perf_hw_id with code in tools/perf/design.txt" * tag 'perf-tools-for-v5.16-2021-11-13' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (67 commits) perf tests: Remove bash constructs from stat_all_pmu.sh perf tests: Remove bash construct from record+zstd_comp_decomp.sh perf test: Remove bash construct from stat_bpf_counters.sh test perf bench futex: Fix memory leak of perf_cpu_map__new() tools arch x86: Sync the msr-index.h copy with the kernel sources tools headers UAPI: Sync drm/i915_drm.h with the kernel sources tools headers UAPI: Sync sound/asound.h with the kernel sources tools headers UAPI: Sync linux/prctl.h with the kernel sources tools headers UAPI: Sync arch prctl headers with the kernel sources perf tools: Add more weak libbpf functions perf bpf: Avoid memory leak from perf_env__insert_btf() perf symbols: Factor out annotation init/exit perf symbols: Bit pack to save a byte perf symbols: Add documentation to 'struct symbol' tools headers UAPI: Sync files changed by new futex_waitv syscall perf test bpf: Use ARRAY_CHECK() instead of ad-hoc equivalent, addressing array_size.cocci warning perf arm-spe: Support hardware-based PID tracing perf arm-spe: Save context ID in record perf arm-spe: Update --switch-events docs in 'perf record' perf arm-spe: Track task context switch for cpu-mode events ...
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Thomas Gleixner authored
Merge tag 'irqchip-fixes-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Address an issue with the SiFive PLIC being unable to EOI a masked interrupt - Move the disable/enable methods in the CSky mpintc to mask/unmask - Fix a regression in the OF irq code where an interrupt-controller property in the same node as an interrupt-map property would get ignored Link: https://lore.kernel.org/all/20211112173459.4015233-1-maz@kernel.org
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- 13 Nov, 2021 3 commits
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git://github.com/terrelln/linuxLinus Torvalds authored
Pull zstd update from Nick Terrell: "Update to zstd-1.4.10. Add myself as the maintainer of zstd and update the zstd version in the kernel, which is now 4 years out of date, to a much more recent zstd release. This includes bug fixes, much more extensive fuzzing, and performance improvements. And generates the kernel zstd automatically from upstream zstd, so it is easier to keep the zstd verison up to date, and we don't fall so far out of date again. This includes 5 commits that update the zstd library version: - Adds a new kernel-style wrapper around zstd. This wrapper API is functionally equivalent to the subset of the current zstd API that is currently used. The wrapper API changes to be kernel style so that the symbols don't collide with zstd's symbols. The update to zstd-1.4.10 maintains the same API and preserves the semantics, so that none of the callers need to be updated. All callers are updated in the commit, because there are zero functional changes. - Adds an indirection for `lib/decompress_unzstd.c` so it doesn't depend on the layout of `lib/zstd/` to include every source file. This allows the next patch to be automatically generated. - Imports the zstd-1.4.10 source code. This commit is automatically generated from upstream zstd (https://github.com/facebook/zstd). - Adds me (terrelln@fb.com) as the maintainer of `lib/zstd`. - Fixes a newly added build warning for clang. The discussion around this patchset has been pretty long, so I've included a FAQ-style summary of the history of the patchset, and why we are taking this approach. Why do we need to update? ------------------------- The zstd version in the kernel is based off of zstd-1.3.1, which is was released August 20, 2017. Since then zstd has seen many bug fixes and performance improvements. And, importantly, upstream zstd is continuously fuzzed by OSS-Fuzz, and bug fixes aren't backported to older versions. So the only way to sanely get these fixes is to keep up to date with upstream zstd. There are no known security issues that affect the kernel, but we need to be able to update in case there are. And while there are no known security issues, there are relevant bug fixes. For example the problem with large kernel decompression has been fixed upstream for over 2 years [1] Additionally the performance improvements for kernel use cases are significant. Measured for x86_64 on my Intel i9-9900k @ 3.6 GHz: - BtrFS zstd compression at levels 1 and 3 is 5% faster - BtrFS zstd decompression+read is 15% faster - SquashFS zstd decompression+read is 15% faster - F2FS zstd compression+write at level 3 is 8% faster - F2FS zstd decompression+read is 20% faster - ZRAM decompression+read is 30% faster - Kernel zstd decompression is 35% faster - Initramfs zstd decompression+build is 5% faster On top of this, there are significant performance improvements coming down the line in the next zstd release, and the new automated update patch generation will allow us to pull them easily. How is the update patch generated? ---------------------------------- The first two patches are preparation for updating the zstd version. Then the 3rd patch in the series imports upstream zstd into the kernel. This patch is automatically generated from upstream. A script makes the necessary changes and imports it into the kernel. The changes are: - Replace all libc dependencies with kernel replacements and rewrite includes. - Remove unncessary portability macros like: #if defined(_MSC_VER). - Use the kernel xxhash instead of bundling it. This automation gets tested every commit by upstream's continuous integration. When we cut a new zstd release, we will submit a patch to the kernel to update the zstd version in the kernel. The automated process makes it easy to keep the kernel version of zstd up to date. The current zstd in the kernel shares the guts of the code, but has a lot of API and minor changes to work in the kernel. This is because at the time upstream zstd was not ready to be used in the kernel envrionment as-is. But, since then upstream zstd has evolved to support being used in the kernel as-is. Why are we updating in one big patch? ------------------------------------- The 3rd patch in the series is very large. This is because it is restructuring the code, so it both deletes the existing zstd, and re-adds the new structure. Future updates will be directly proportional to the changes in upstream zstd since the last import. They will admittidly be large, as zstd is an actively developed project, and has hundreds of commits between every release. However, there is no other great alternative. One option ruled out is to replay every upstream zstd commit. This is not feasible for several reasons: - There are over 3500 upstream commits since the zstd version in the kernel. - The automation to automatically generate the kernel update was only added recently, so older commits cannot easily be imported. - Not every upstream zstd commit builds. - Only zstd releases are "supported", and individual commits may have bugs that were fixed before a release. Another option to reduce the patch size would be to first reorganize to the new file structure, and then apply the patch. However, the current kernel zstd is formatted with clang-format to be more "kernel-like". But, the new method imports zstd as-is, without additional formatting, to allow for closer correlation with upstream, and easier debugging. So the patch wouldn't be any smaller. It also doesn't make sense to import upstream zstd commit by commit going forward. Upstream zstd doesn't support production use cases running of the development branch. We have a lot of post-commit fuzzing that catches many bugs, so indiviudal commits may be buggy, but fixed before a release. So going forward, I intend to import every (important) zstd release into the Kernel. So, while it isn't ideal, updating in one big patch is the only patch I see forward. Who is responsible for this code? --------------------------------- I am. This patchset adds me as the maintainer for zstd. Previously, there was no tree for zstd patches. Because of that, there were several patches that either got ignored, or took a long time to merge, since it wasn't clear which tree should pick them up. I'm officially stepping up as maintainer, and setting up my tree as the path through which zstd patches get merged. I'll make sure that patches to the kernel zstd get ported upstream, so they aren't erased when the next version update happens. How is this code tested? ------------------------ I tested every caller of zstd on x86_64 (BtrFS, ZRAM, SquashFS, F2FS, Kernel, InitRAMFS). I also tested Kernel & InitRAMFS on i386 and aarch64. I checked both performance and correctness. Also, thanks to many people in the community who have tested these patches locally. Lastly, this code will bake in linux-next before being merged into v5.16. Why update to zstd-1.4.10 when zstd-1.5.0 has been released? ------------------------------------------------------------ This patchset has been outstanding since 2020, and zstd-1.4.10 was the latest release when it was created. Since the update patch is automatically generated from upstream, I could generate it from zstd-1.5.0. However, there were some large stack usage regressions in zstd-1.5.0, and are only fixed in the latest development branch. And the latest development branch contains some new code that needs to bake in the fuzzer before I would feel comfortable releasing to the kernel. Once this patchset has been merged, and we've released zstd-1.5.1, we can update the kernel to zstd-1.5.1, and exercise the update process. You may notice that zstd-1.4.10 doesn't exist upstream. This release is an artifical release based off of zstd-1.4.9, with some fixes for the kernel backported from the development branch. I will tag the zstd-1.4.10 release after this patchset is merged, so the Linux Kernel is running a known version of zstd that can be debugged upstream. Why was a wrapper API added? ---------------------------- The first versions of this patchset migrated the kernel to the upstream zstd API. It first added a shim API that supported the new upstream API with the old code, then updated callers to use the new shim API, then transitioned to the new code and deleted the shim API. However, Cristoph Hellwig suggested that we transition to a kernel style API, and hide zstd's upstream API behind that. This is because zstd's upstream API is supports many other use cases, and does not follow the kernel style guide, while the kernel API is focused on the kernel's use cases, and follows the kernel style guide. Where is the previous discussion? --------------------------------- Links for the discussions of the previous versions of the patch set below. The largest changes in the design of the patchset are driven by the discussions in v11, v5, and v1. Sorry for the mix of links, I couldn't find most of the the threads on lkml.org" Link: https://lkml.org/lkml/2020/9/29/27 [1] Link: https://www.spinics.net/lists/linux-crypto/msg58189.html [v12] Link: https://lore.kernel.org/linux-btrfs/20210430013157.747152-1-nickrterrell@gmail.com/ [v11] Link: https://lore.kernel.org/lkml/20210426234621.870684-2-nickrterrell@gmail.com/ [v10] Link: https://lore.kernel.org/linux-btrfs/20210330225112.496213-1-nickrterrell@gmail.com/ [v9] Link: https://lore.kernel.org/linux-f2fs-devel/20210326191859.1542272-1-nickrterrell@gmail.com/ [v8] Link: https://lkml.org/lkml/2020/12/3/1195 [v7] Link: https://lkml.org/lkml/2020/12/2/1245 [v6] Link: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/ [v5] Link: https://www.spinics.net/lists/linux-btrfs/msg105783.html [v4] Link: https://lkml.org/lkml/2020/9/23/1074 [v3] Link: https://www.spinics.net/lists/linux-btrfs/msg105505.html [v2] Link: https://lore.kernel.org/linux-btrfs/20200916034307.2092020-1-nickrterrell@gmail.com/ [v1] Signed-off-by:Nick Terrell <terrelln@fb.com> Tested By: Paul Jones <paul@pauljones.id.au> Tested-by:
Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64 Tested-by:
Jean-Denis Girard <jd.girard@sysnux.pf> * tag 'zstd-for-linus-v5.16' of git://github.com/terrelln/linux: lib: zstd: Add cast to silence clang's -Wbitwise-instead-of-logical MAINTAINERS: Add maintainer entry for zstd lib: zstd: Upgrade to latest upstream zstd version 1.4.10 lib: zstd: Add decompress_sources.h for decompress_unzstd lib: zstd: Add kernel-specific API
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git://github.com/davidhildenbrand/linuxLinus Torvalds authored
Pull virtio-mem update from David Hildenbrand: "Support the VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE feature in virtio-mem, now that "accidential" access to logically unplugged memory inside added Linux memory blocks is no longer possible, because we: - Removed /dev/kmem in commit bbcd53c9 ("drivers/char: remove /dev/kmem for good") - Disallowed access to virtio-mem device memory via /dev/mem in commit 2128f4e2 ("virtio-mem: disallow mapping virtio-mem memory via /dev/mem") - Sanitized access to virtio-mem device memory via /proc/kcore in commit 0daa322b ("fs/proc/kcore: don't read offline sections, logically offline pages and hwpoisoned pages") - Sanitized access to virtio-mem device memory via /proc/vmcore in commit ce281462 ("virtio-mem: kdump mode to sanitize /proc/vmcore access") The new VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE feature that will be required by some hypervisors implementing virtio-mem in the near future, so let's support it now that we safely can" * tag 'virtio-mem-for-5.16' of git://github.com/davidhildenbrand/linux: virtio-mem: support VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE
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James Clark authored
The tests were passing but without testing and were printing the following: $ ./perf test -v 90 90: perf all PMU test : --- start --- test child forked, pid 51650 Testing cpu/branch-instructions/ ./tests/shell/stat_all_pmu.sh: 10: [: Performance counter stats for 'true': 137,307 cpu/branch-instructions/ 0.001686672 seconds time elapsed 0.001376000 seconds user 0.000000000 seconds sys: unexpected operator Changing the regexes to a grep works in sh and prints this: $ ./perf test -v 90 90: perf all PMU test : --- start --- test child forked, pid 60186 [...] Testing tlb_flush.stlb_any test child finished with 0 ---- end ---- perf all PMU test: Ok Signed-off-by:James Clark <james.clark@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Yonghong Song <yhs@fb.com> Cc: bpf@vger.kernel.org Cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/20211028134828.65774-4-james.clark@arm.comSigned-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com>
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