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[PATCH v1 1/2] Add polling support to pidfd

by Joel Fernandes (Google)

pidfd are file descriptors referring to a process created with the CLONE_PIDFD clone(2) flag. Android low memory killer (LMK) needs pidfd polling support to replace code that currently checks for existence of /proc/pid for knowing that a process that is signalled to be killed has died, which is both racy and slow. The pidfd poll approach is race-free, and also allows the LMK to do other things (such as by polling on other fds) while awaiting the process being killed to die. It prevents a situation where a PID is reused between when LMK sends a kill signal and checks for existence of the PID, since the wrong PID is now possibly checked for existence. In this patch, we follow the same existing mechanism in the kernel used when the parent of the task group is to be notified (do_notify_parent). This is when the tasks waiting on a poll of pidfd are also awakened. We have decided to include the waitqueue in struct pid for the following reasons: 1. The wait queue has to survive for the lifetime of the poll. Including it in task_struct would not be option in this case because the task can be reaped and destroyed before the poll returns. 2. By including the struct pid for the waitqueue means that during de_thread(), the new thread group leader automatically gets the new waitqueue/pid even though its task_struct is different. Appropriate test cases are added in the second patch to provide coverage of all the cases the patch is handling. Andy had a similar patch [1] in the past which was a good reference however this patch tries to handle different situations properly related to thread group existence, and how/where it notifies. And also solves other bugs (waitqueue lifetime). Daniel had a similar patch [2] recently which this patch supercedes. [1] https://lore.kernel.org/patchwork/patch/345098/ [2] https://lore.kernel.org/lkml/20181029175322.189042-1-dancol@google.com/ Cc: luto(a)amacapital.net Cc: rostedt(a)goodmis.org Cc: dancol(a)google.com Cc: sspatil(a)google.com Cc: christian(a)brauner.io Cc: jannh(a)google.com Cc: surenb(a)google.com Cc: timmurray(a)google.com Cc: Jonathan Kowalski <bl0pbl33p(a)gmail.com> Cc: torvalds(a)linux-foundation.org Cc: kernel-team(a)android.com Co-developed-by: Daniel Colascione <dancol(a)google.com> Signed-off-by: Joel Fernandes (Google) <joel(a)joelfernandes.org> --- RFC -> v1: * Based on CLONE_PIDFD patches: https://lwn.net/Articles/786244/ * Updated selftests. * Renamed poll wake function to do_notify_pidfd. * Removed depending on EXIT flags * Removed POLLERR flag since semantics are controversial and we don't have usecases for it right now (later we can add if there's a need for it). include/linux/pid.h | 3 +++ kernel/fork.c | 33 +++++++++++++++++++++++++++++++++ kernel/pid.c | 2 ++ kernel/signal.c | 14 ++++++++++++++ 4 files changed, 52 insertions(+) diff --git a/include/linux/pid.h b/include/linux/pid.h index 3c8ef5a199ca..1484db6ca8d1 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -3,6 +3,7 @@ #define _LINUX_PID_H #include <linux/rculist.h> +#include <linux/wait.h> enum pid_type { @@ -60,6 +61,8 @@ struct pid unsigned int level; /* lists of tasks that use this pid */ struct hlist_head tasks[PIDTYPE_MAX]; + /* wait queue for pidfd notifications */ + wait_queue_head_t wait_pidfd; struct rcu_head rcu; struct upid numbers[1]; }; diff --git a/kernel/fork.c b/kernel/fork.c index 5525837ed80e..fb3b614f6456 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1685,8 +1685,41 @@ static void pidfd_show_fdinfo(struct seq_file *m, struct file *f) } #endif +static unsigned int pidfd_poll(struct file *file, struct poll_table_struct *pts) +{ + struct task_struct *task; + struct pid *pid; + int poll_flags = 0; + + /* + * tasklist_lock must be held because to avoid racing with + * changes in exit_state and wake up. Basically to avoid: + * + * P0: read exit_state = 0 + * P1: write exit_state = EXIT_DEAD + * P1: Do a wake up - wq is empty, so do nothing + * P0: Queue for polling - wait forever. + */ + read_lock(&tasklist_lock); + pid = file->private_data; + task = pid_task(pid, PIDTYPE_PID); + WARN_ON_ONCE(task && !thread_group_leader(task)); + + if (!task || (task->exit_state && thread_group_empty(task))) + poll_flags = POLLIN | POLLRDNORM; + + if (!poll_flags) + poll_wait(file, &pid->wait_pidfd, pts); + + read_unlock(&tasklist_lock); + + return poll_flags; +} + + const struct file_operations pidfd_fops = { .release = pidfd_release, + .poll = pidfd_poll, #ifdef CONFIG_PROC_FS .show_fdinfo = pidfd_show_fdinfo, #endif diff --git a/kernel/pid.c b/kernel/pid.c index 20881598bdfa..5c90c239242f 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -214,6 +214,8 @@ struct pid *alloc_pid(struct pid_namespace *ns) for (type = 0; type < PIDTYPE_MAX; ++type) INIT_HLIST_HEAD(&pid->tasks[type]); + init_waitqueue_head(&pid->wait_pidfd); + upid = pid->numbers + ns->level; spin_lock_irq(&pidmap_lock); if (!(ns->pid_allocated & PIDNS_ADDING)) diff --git a/kernel/signal.c b/kernel/signal.c index 1581140f2d99..16e7718316e5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1800,6 +1800,17 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type) return ret; } +static void do_notify_pidfd(struct task_struct *task) +{ + struct pid *pid; + + lockdep_assert_held(&tasklist_lock); + + pid = get_task_pid(task, PIDTYPE_PID); + wake_up_all(&pid->wait_pidfd); + put_pid(pid); +} + /* * Let a parent know about the death of a child. * For a stopped/continued status change, use do_notify_parent_cldstop instead. @@ -1823,6 +1834,9 @@ bool do_notify_parent(struct task_struct *tsk, int sig) BUG_ON(!tsk->ptrace && (tsk->group_leader != tsk || !thread_group_empty(tsk))); + /* Wake up all pidfd waiters */ + do_notify_pidfd(tsk); + if (sig != SIGCHLD) { /* * This is only possible if parent == real_parent. -- 2.21.0.593.g511ec345e18-goog

6 years, 7 months

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[PATCH 0/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation

by Nicolai Stange

Hi, this series is the result of the discussion to the RFC patch found at [1]. The goal is to make x86' ftrace_int3_handler() not to simply skip over the trapping instruction as this is problematic in the context of the live patching consistency model. For details, c.f. the commit message of [3/4] ("x86/ftrace: make ftrace_int3_handler() not to skip fops invocation"). Everything is based on v5.1-rc6, please let me know in case you want me to rebase on somehing else. For x86_64, the live patching selftest added in [4/4] succeeds with this series applied and fails without it. On 32 bits I only compile-tested. checkpatch reports warnings about - an overlong line in assembly -- I chose to ignore that - MAINTAINERS perhaps needing updates due to the new files arch/x86/kernel/ftrace_int3_stubs.S and tools/testing/selftests/livepatch/test-livepatch-vs-ftrace.sh. As the existing arch/x86/kernel/ftrace_{32,64}.S haven't got an explicit entry either, this one is probably Ok? The selftest definitely is. Changes to the RFC patch: - s/trampoline/stub/ to avoid confusion with the ftrace_ops' trampolines, - use a fixed size stack kept in struct thread_info for passing the (adjusted) ->ip values from ftrace_int3_handler() to the stubs, - provide one stub for each of the two possible jump targets and hardcode those, - add the live patching selftest. Thanks, Nicolai Nicolai Stange (4): x86/thread_info: introduce ->ftrace_int3_stack member ftrace: drop 'static' qualifier from ftrace_ops_list_func() x86/ftrace: make ftrace_int3_handler() not to skip fops invocation selftests/livepatch: add "ftrace a live patched function" test arch/x86/include/asm/thread_info.h | 11 +++ arch/x86/kernel/Makefile | 1 + arch/x86/kernel/asm-offsets.c | 8 +++ arch/x86/kernel/ftrace.c | 79 +++++++++++++++++++--- arch/x86/kernel/ftrace_int3_stubs.S | 61 +++++++++++++++++ kernel/trace/ftrace.c | 8 +-- tools/testing/selftests/livepatch/Makefile | 3 +- .../livepatch/test-livepatch-vs-ftrace.sh | 44 ++++++++++++ 8 files changed, 199 insertions(+), 16 deletions(-) create mode 100644 arch/x86/kernel/ftrace_int3_stubs.S create mode 100755 tools/testing/selftests/livepatch/test-livepatch-vs-ftrace.sh -- 2.13.7

6 years, 7 months

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Re: [PATCH 3/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation

by Andy Lutomirski

On Mon, Apr 29, 2019 at 11:53 AM Linus Torvalds <torvalds(a)linux-foundation.org> wrote: > > > > On Mon, Apr 29, 2019, 11:42 Andy Lutomirski <luto(a)kernel.org> wrote: >> >> >> I'm less than 100% convinced about this argument. Sure, an NMI right >> there won't cause a problem. But an NMI followed by an interrupt will >> kill us if preemption is on. I can think of three solutions: > > > No, because either the sti shadow disables nmi too (that's the case on some CPUs at least) or the iret from nmi does. > > Otherwise you could never trust the whole sti shadow thing - and it very much is part of the architecture. > Is this documented somewhere? And do you actually believe that this is true under KVM, Hyper-V, etc? As I recall, Andrew Cooper dug in to the way that VMX dealt with this stuff and concluded that the SDM was blatantly wrong in many cases, which leads me to believe that Xen HVM/PVH is the *only* hypervisor that gets it right. Steven's point about batched updates is quite valid, though. My personal favorite solution to this whole mess is to rework the whole thing so that the int3 handler simply returns and retries and to replace the sync_core() broadcast with an SMI broadcast. I don't know whether this will actually work on real CPUs and on VMs and whether it's going to crash various BIOSes out there.

6 years, 7 months

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Re: [PATCH 3/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation

by Linus Torvalds

On Mon, Apr 29, 2019 at 12:02 PM Linus Torvalds <torvalds(a)linux-foundation.org> wrote: > > If nmi were to break it, it would be a cpu bug. I'm pretty sure I've > seen the "shadow stops even nmi" documented for some uarch, but as > mentioned it's not necessarily the only way to guarantee the shadow. In fact, the documentation is simply the official Intel instruction docs for "STI": The IF flag and the STI and CLI instructions do not prohibit the generation of exceptions and NMI interrupts. NMI interrupts (and SMIs) may be blocked for one macroinstruction following an STI. note the "may be blocked". As mentioned, that's just one option for not having NMI break the STI shadow guarantee, but it's clearly one that Intel has done at times, and clearly even documents as having done so. There is absolutely no question that the sti shadow is real, and that people have depended on it for _decades_. It would be a horrible errata if the shadow can just be made to go away by randomly getting an NMI or SMI. Linus

6 years, 7 months

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Re: [PATCH 3/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation

by Steven Rostedt

On Mon, 29 Apr 2019 11:59:04 -0700 Linus Torvalds <torvalds(a)linux-foundation.org> wrote: > I really don't care. Just do what I suggested, and if you have numbers to > show problems, then maybe I'll care. > Are you suggesting that I rewrite the code to do it one function at a time? This has always been batch mode. This is not something new. The function tracer has been around longer than the text poke code. > Right now you're just making excuses for this. I described the solution > months ago, now I've written a patch, if that's not good enough then we can > just skip this all entirely. > > Honestly, if you need to rewrite tens of thousands of calls, maybe you're > doing something wrong? > # cd /sys/kernel/debug/tracing # cat available_filter_functions | wc -l 45856 # cat enabled_functions | wc -l 0 # echo function > current_tracer # cat enabled_functions | wc -l 45856 There, I just enabled 45,856 function call sites in one shot! How else do you want to update them? Every function in the kernel has a nop, that turns into a call to the ftrace_handler, if I add another user of that code, it will change each one as well. -- Steve

6 years, 7 months

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[PATCH for 5.2 12/12] rseq/selftests: add -no-integrated-as for clang

by Mathieu Desnoyers

Ongoing work for asm goto support from clang requires the -no-integrated-as compiler flag. This compiler flag is present in the toplevel kernel Makefile, but is not replicated for selftests. Add it specifically for the rseq selftest which requires asm goto. Link: https://reviews.llvm.org/D56571 Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Nick Desaulniers <ndesaulniers(a)google.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/Makefile | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile index c30c52e1d0d2..d6469535630a 100644 --- a/tools/testing/selftests/rseq/Makefile +++ b/tools/testing/selftests/rseq/Makefile @@ -1,5 +1,11 @@ # SPDX-License-Identifier: GPL-2.0+ OR MIT -CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ + +ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) +CLANG_FLAGS += -no-integrated-as +endif + +CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ \ + $(CLANG_FLAGS) LDLIBS += -lpthread # Own dependencies because we only want to build against 1st prerequisite, but -- 2.11.0

6 years, 7 months

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[PATCH for 5.2 09/12] rseq/selftests: aarch64 code signature: handle big-endian environment

by Mathieu Desnoyers

Handle compiling with -mbig-endian on aarch64, which generates binaries with mixed code vs data endianness (little endian code, big endian data). Else mismatch between code endianness for the generated signatures and data endianness for the RSEQ_SIG parameter passed to the rseq registration will trigger application segmentation faults when the kernel try to abort rseq critical sections. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> Acked-by: Will Deacon <will.deacon(a)arm.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/rseq-arm64.h | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq-arm64.h b/tools/testing/selftests/rseq/rseq-arm64.h index b41a2a48e965..200dae9e4208 100644 --- a/tools/testing/selftests/rseq/rseq-arm64.h +++ b/tools/testing/selftests/rseq/rseq-arm64.h @@ -6,7 +6,20 @@ * (C) Copyright 2018 - Will Deacon <will.deacon(a)arm.com> */ -#define RSEQ_SIG 0xd428bc00 /* BRK #0x45E0 */ +/* + * aarch64 -mbig-endian generates mixed endianness code vs data: + * little-endian code and big-endian data. Ensure the RSEQ_SIG signature + * matches code endianness. + */ +#define RSEQ_SIG_CODE 0xd428bc00 /* BRK #0x45E0. */ + +#ifdef __AARCH64EB__ +#define RSEQ_SIG_DATA 0x00bc28d4 /* BRK #0x45E0. */ +#else +#define RSEQ_SIG_DATA RSEQ_SIG_CODE +#endif + +#define RSEQ_SIG RSEQ_SIG_DATA #define rseq_smp_mb() __asm__ __volatile__ ("dmb ish" ::: "memory") #define rseq_smp_rmb() __asm__ __volatile__ ("dmb ishld" ::: "memory") @@ -121,7 +134,7 @@ do { \ #define RSEQ_ASM_DEFINE_ABORT(label, abort_label) \ " b 222f\n" \ - " .inst " __rseq_str(RSEQ_SIG) "\n" \ + " .inst " __rseq_str(RSEQ_SIG_CODE) "\n" \ __rseq_str(label) ":\n" \ " b %l[" __rseq_str(abort_label) "]\n" \ "222:\n" -- 2.11.0

6 years, 7 months

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[PATCH for 5.2 06/12] rseq/selftests: x86: use ud1 instruction as RSEQ_SIG opcode

by Mathieu Desnoyers

Use ud1 as the guard instruction for the restartable sequence abort handler. Its benefit compared to nopl is to trap execution if the program ends up trying to execute it by mistake, which makes debugging easier. The 4-byte signature per se is unchanged (it is the instruction operand). Only the opcode is changed from nopl to ud1. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> Suggested-by: Peter Zijlstra <peterz(a)infradead.org> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/rseq-x86.h | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h index 03095236f6fa..b2da6004fe30 100644 --- a/tools/testing/selftests/rseq/rseq-x86.h +++ b/tools/testing/selftests/rseq/rseq-x86.h @@ -7,6 +7,13 @@ #include <stdint.h> +/* + * RSEQ_SIG is used with the following reserved undefined instructions, which + * trap in user-space: + * + * x86-32: 0f b9 3d 53 30 05 53 ud1 0x53053053,%edi + * x86-64: 0f b9 3d 53 30 05 53 ud1 0x53053053(%rip),%edi + */ #define RSEQ_SIG 0x53053053 /* @@ -88,8 +95,8 @@ do { \ #define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ ".pushsection __rseq_failure, \"ax\"\n\t" \ - /* Disassembler-friendly signature: nopl <sig>(%rip). */\ - ".byte 0x0f, 0x1f, 0x05\n\t" \ + /* Disassembler-friendly signature: ud1 <sig>(%rip),%edi. */ \ + ".byte 0x0f, 0xb9, 0x3d\n\t" \ ".long " __rseq_str(RSEQ_SIG) "\n\t" \ __rseq_str(label) ":\n\t" \ teardown \ @@ -609,8 +616,8 @@ do { \ #define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ ".pushsection __rseq_failure, \"ax\"\n\t" \ - /* Disassembler-friendly signature: nopl <sig>. */ \ - ".byte 0x0f, 0x1f, 0x05\n\t" \ + /* Disassembler-friendly signature: ud1 <sig>,%edi. */ \ + ".byte 0x0f, 0xb9, 0x3d\n\t" \ ".long " __rseq_str(RSEQ_SIG) "\n\t" \ __rseq_str(label) ":\n\t" \ teardown \ -- 2.11.0

6 years, 7 months

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[PATCH for 5.2 05/12] rseq/selftests: s390: use jg instruction for jumps outside of the asm

by Mathieu Desnoyers

The branch target range of the "j" instruction is 64K, which is not enough for the general case. Suggested-by: Martin Schwidefsky <schwidefsky(a)de.ibm.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/rseq-s390.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq-s390.h b/tools/testing/selftests/rseq/rseq-s390.h index fbb97815d71c..7c4f3a70b6c7 100644 --- a/tools/testing/selftests/rseq/rseq-s390.h +++ b/tools/testing/selftests/rseq/rseq-s390.h @@ -117,14 +117,14 @@ do { \ ".long " __rseq_str(RSEQ_SIG) "\n\t" \ __rseq_str(label) ":\n\t" \ teardown \ - "j %l[" __rseq_str(abort_label) "]\n\t" \ + "jg %l[" __rseq_str(abort_label) "]\n\t" \ ".popsection\n\t" #define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ ".pushsection __rseq_failure, \"ax\"\n\t" \ __rseq_str(label) ":\n\t" \ teardown \ - "j %l[" __rseq_str(cmpfail_label) "]\n\t" \ + "jg %l[" __rseq_str(cmpfail_label) "]\n\t" \ ".popsection\n\t" static inline __attribute__((always_inline)) -- 2.11.0

6 years, 7 months

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[PATCH for 5.2 03/12] rseq/selftests: Introduce __rseq_cs_ptr_array, rename __rseq_table to __rseq_cs

by Mathieu Desnoyers

The entries within __rseq_table are aligned on 32 bytes due to linux/rseq.h struct rseq_cs uapi requirements, but the start of the __rseq_table section is not guaranteed to be 32-byte aligned. It can cause padding to be added at the start of the section, which makes it hard to use as an array of items by debuggers. Considering that __rseq_table does not really consist of a table due to the presence of padding, rename this section to __rseq_cs. Create a new __rseq_cs_ptr_array section which contains 64-bit packed pointers to entries within the __rseq_cs section. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/rseq-arm.h | 32 +++++++++++++++++-------------- tools/testing/selftests/rseq/rseq-arm64.h | 9 ++++++--- tools/testing/selftests/rseq/rseq-mips.h | 32 +++++++++++++++++-------------- tools/testing/selftests/rseq/rseq-ppc.h | 22 +++++++++++++-------- tools/testing/selftests/rseq/rseq-s390.h | 18 +++++++++++------ tools/testing/selftests/rseq/rseq-x86.h | 19 ++++++++++++------ 6 files changed, 81 insertions(+), 51 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h index 17e8d231943a..5f262c54364f 100644 --- a/tools/testing/selftests/rseq/rseq-arm.h +++ b/tools/testing/selftests/rseq/rseq-arm.h @@ -30,24 +30,28 @@ do { \ #include "rseq-skip.h" #else /* !RSEQ_SKIP_FASTPATH */ -#define __RSEQ_ASM_DEFINE_TABLE(version, flags, start_ip, \ +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \ post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".word " __rseq_str(label) "b, 0x0\n\t" \ ".popsection\n\t" -#define RSEQ_ASM_DEFINE_TABLE(start_ip, post_commit_ip, abort_ip) \ - __RSEQ_ASM_DEFINE_TABLE(0x0, 0x0, start_ip, \ +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ (post_commit_ip - start_ip), abort_ip) /* * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ @@ -99,7 +103,7 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -166,7 +170,7 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -237,7 +241,7 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu) rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) #endif @@ -292,7 +296,7 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -367,7 +371,7 @@ int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -443,7 +447,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -527,7 +531,7 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -651,7 +655,7 @@ int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) diff --git a/tools/testing/selftests/rseq/rseq-arm64.h b/tools/testing/selftests/rseq/rseq-arm64.h index 2079f71e0ca2..b41a2a48e965 100644 --- a/tools/testing/selftests/rseq/rseq-arm64.h +++ b/tools/testing/selftests/rseq/rseq-arm64.h @@ -82,13 +82,16 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \ post_commit_offset, abort_ip) \ - " .pushsection __rseq_table, \"aw\"\n" \ + " .pushsection __rseq_cs, \"aw\"\n" \ " .balign 32\n" \ __rseq_str(label) ":\n" \ " .long " __rseq_str(version) ", " __rseq_str(flags) "\n" \ " .quad " __rseq_str(start_ip) ", " \ __rseq_str(post_commit_offset) ", " \ __rseq_str(abort_ip) "\n" \ + " .popsection\n\t" \ + " .pushsection __rseq_cs_ptr_array, \"aw\"\n" \ + " .quad " __rseq_str(label) "b\n" \ " .popsection\n" #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ @@ -99,8 +102,8 @@ do { \ * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ diff --git a/tools/testing/selftests/rseq/rseq-mips.h b/tools/testing/selftests/rseq/rseq-mips.h index 25d10ff54769..fe3eabcdcbe5 100644 --- a/tools/testing/selftests/rseq/rseq-mips.h +++ b/tools/testing/selftests/rseq/rseq-mips.h @@ -54,26 +54,30 @@ do { \ # error unsupported _MIPS_SZLONG #endif -#define __RSEQ_ASM_DEFINE_TABLE(version, flags, start_ip, \ +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \ post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \ LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \ LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + LONG " " U32_U64_PAD(__rseq_str(label) "b") "\n\t" \ ".popsection\n\t" -#define RSEQ_ASM_DEFINE_TABLE(start_ip, post_commit_ip, abort_ip) \ - __RSEQ_ASM_DEFINE_TABLE(0x0, 0x0, start_ip, \ +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ (post_commit_ip - start_ip), abort_ip) /* * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ @@ -127,7 +131,7 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -192,7 +196,7 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -261,7 +265,7 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu) rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) #endif @@ -316,7 +320,7 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -389,7 +393,7 @@ int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -463,7 +467,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -543,7 +547,7 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) @@ -664,7 +668,7 @@ int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, rseq_workaround_gcc_asm_size_guess(); __asm__ __volatile__ goto ( - RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) #ifdef RSEQ_COMPARE_TWICE RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) diff --git a/tools/testing/selftests/rseq/rseq-ppc.h b/tools/testing/selftests/rseq/rseq-ppc.h index 24f95649d71e..9df18487fa9f 100644 --- a/tools/testing/selftests/rseq/rseq-ppc.h +++ b/tools/testing/selftests/rseq/rseq-ppc.h @@ -33,8 +33,8 @@ do { \ #else /* !RSEQ_SKIP_FASTPATH */ /* - * The __rseq_table section can be used by debuggers to better handle - * single-stepping through the restartable critical sections. + * The __rseq_cs_ptr_array and __rseq_cs sections can be used by debuggers to + * better handle single-stepping through the restartable critical sections. */ #ifdef __PPC64__ @@ -46,11 +46,14 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".quad " __rseq_str(label) "b\n\t" \ ".popsection\n\t" #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ @@ -67,8 +70,8 @@ do { \ * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ @@ -85,20 +88,23 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ /* 32-bit only supported on BE */ \ ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".long 0x0, " __rseq_str(label) "b\n\t" \ ".popsection\n\t" /* * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ diff --git a/tools/testing/selftests/rseq/rseq-s390.h b/tools/testing/selftests/rseq/rseq-s390.h index b8b5b6f900af..fbb97815d71c 100644 --- a/tools/testing/selftests/rseq/rseq-s390.h +++ b/tools/testing/selftests/rseq/rseq-s390.h @@ -37,19 +37,22 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".quad " __rseq_str(label) "b\n\t" \ ".popsection\n\t" /* * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ @@ -61,19 +64,22 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".long 0x0, " __rseq_str(label) "b\n\t" \ ".popsection\n\t" /* * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h index 0668608d3674..03095236f6fa 100644 --- a/tools/testing/selftests/rseq/rseq-x86.h +++ b/tools/testing/selftests/rseq/rseq-x86.h @@ -47,13 +47,17 @@ do { \ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".quad " __rseq_str(label) "b\n\t" \ ".popsection\n\t" + #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ (post_commit_ip - start_ip), abort_ip) @@ -62,8 +66,8 @@ do { \ * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ @@ -566,11 +570,14 @@ do { \ */ #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ start_ip, post_commit_offset, abort_ip) \ - ".pushsection __rseq_table, \"aw\"\n\t" \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ ".balign 32\n\t" \ __rseq_str(label) ":\n\t" \ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".long " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".long " __rseq_str(label) "b, 0x0\n\t" \ ".popsection\n\t" #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ @@ -581,8 +588,8 @@ do { \ * Exit points of a rseq critical section consist of all instructions outside * of the critical section where a critical section can either branch to or * reach through the normal course of its execution. The abort IP and the - * post-commit IP are already part of the __rseq_table section and should not - * be explicitly defined as additional exit points. Knowing all exit points is + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is * useful to assist debuggers stepping over the critical section. */ #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ -- 2.11.0

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