Chen Zhongjin 98bada8fa0 x86/unwind/orc: Fix unreliable stack dump with gcov ... [ Upstream commit 230db82413 ] When a console stack dump is initiated with CONFIG_GCOV_PROFILE_ALL enabled, show_trace_log_lvl() gets out of sync with the ORC unwinder, causing the stack trace to show all text addresses as unreliable: # echo l > /proc/sysrq-trigger [ 477.521031] sysrq: Show backtrace of all active CPUs [ 477.523813] NMI backtrace for cpu 0 [ 477.524492] CPU: 0 PID: 1021 Comm: bash Not tainted 6.0.0 #65 [ 477.525295] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014 [ 477.526439] Call Trace: [ 477.526854] <TASK> [ 477.527216] ? dump_stack_lvl+0xc7/0x114 [ 477.527801] ? dump_stack+0x13/0x1f [ 477.528331] ? nmi_cpu_backtrace.cold+0xb5/0x10d [ 477.528998] ? lapic_can_unplug_cpu+0xa0/0xa0 [ 477.529641] ? nmi_trigger_cpumask_backtrace+0x16a/0x1f0 [ 477.530393] ? arch_trigger_cpumask_backtrace+0x1d/0x30 [ 477.531136] ? sysrq_handle_showallcpus+0x1b/0x30 [ 477.531818] ? __handle_sysrq.cold+0x4e/0x1ae [ 477.532451] ? write_sysrq_trigger+0x63/0x80 [ 477.533080] ? proc_reg_write+0x92/0x110 [ 477.533663] ? vfs_write+0x174/0x530 [ 477.534265] ? handle_mm_fault+0x16f/0x500 [ 477.534940] ? ksys_write+0x7b/0x170 [ 477.535543] ? __x64_sys_write+0x1d/0x30 [ 477.536191] ? do_syscall_64+0x6b/0x100 [ 477.536809] ? entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 477.537609] </TASK> This happens when the compiled code for show_stack() has a single word on the stack, and doesn't use a tail call to show_stack_log_lvl(). (CONFIG_GCOV_PROFILE_ALL=y is the only known case of this.) Then the __unwind_start() skip logic hits an off-by-one bug and fails to unwind all the way to the intended starting frame. Fix it by reverting the following commit: f1d9a2abff ("x86/unwind/orc: Don't skip the first frame for inactive tasks") The original justification for that commit no longer exists. That original issue was later fixed in a different way, with the following commit: f2ac57a4c4 ("x86/unwind/orc: Fix inactive tasks with stack pointer in %sp on GCC 10 compiled kernels") Fixes: f1d9a2abff ("x86/unwind/orc: Don't skip the first frame for inactive tasks") Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com> [jpoimboe: rewrite commit log] Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-11-03 23:59:16 +09:00
..
acpi	x86: Prepare asm files for straight-line-speculation	2022-05-15 20:18:49 +02:00
apic	x86: Fix return value of __setup handlers	2022-06-09 10:22:53 +02:00
cpu	x86/topology: Fix duplicated core ID within a package	2022-10-29 10:12:55 +02:00
fpu	x86/fpu: Prevent FPU state corruption	2022-05-12 12:30:02 +02:00
kprobes	x86/kprobes: Fix JNG/JNLE emulation	2022-08-25 11:39:57 +02:00
.gitignore
alternative.c	x86/alternative: Fix race in try_get_desc()	2022-10-05 10:39:44 +02:00
amd_gart_64.c	x86/amd_gart: don't set failed sg dma_address to DMA_MAPPING_ERROR	2021-08-09 17:13:06 +02:00
amd_nb.c	hwmon: (k10temp) Add support for yellow carp	2021-08-27 13:54:58 -07:00
aperture_64.c	memblock: make memblock_find_in_range method private	2021-09-03 09:58:17 -07:00
apm_32.c	x86: Fix various typos in comments, take #2	2021-03-21 23:50:28 +01:00
asm-offsets_32.c	x86/stackprotector/32: Make the canary into a regular percpu variable	2021-03-08 13:19:05 +01:00
asm-offsets_64.c	x86/xen: Drop USERGS_SYSRET64 paravirt call	2021-02-10 12:32:07 +01:00
asm-offsets.c	x86/paravirt: Switch iret pvops to ALTERNATIVE	2021-03-11 19:58:54 +01:00
audit_64.c
bootflag.c
cc_platform.c	x86/sev: Add an x86 version of cc_platform_has()	2021-11-18 19:17:21 +01:00
check.c
cpuid.c	smp: Cleanup smp_call_function*()	2020-11-24 16:47:49 +01:00
crash_core_32.c
crash_core_64.c
crash_dump_32.c	x86/crashdump/32: Simplify copy_oldmem_page()	2020-11-24 14:42:09 +01:00
crash_dump_64.c
crash.c	x86/crash: Remove crash_reserve_low_1M()	2021-06-07 12:14:45 +02:00
devicetree.c	x86/devicetree: Fix the ioapic interrupt type table	2020-10-28 20:26:24 +01:00
doublefault_32.c	x86/stackprotector/32: Make the canary into a regular percpu variable	2021-03-08 13:19:05 +01:00
dumpstack_32.c
dumpstack_64.c	x86/mm/64: Improve stack overflow warnings	2021-11-18 19:16:10 +01:00
dumpstack.c	x86/dumpstack: use %pSb/%pBb for backtrace printing	2021-07-08 11:48:22 -07:00
e820.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-16 14:23:45 +01:00
early_printk.c
early-quirks.c	x86/gpu: Reserve stolen memory for first integrated Intel GPU	2022-01-27 11:02:51 +01:00
ebda.c
eisa.c
espfix_64.c
ftrace_32.S	x86: Prepare asm files for straight-line-speculation	2022-05-15 20:18:49 +02:00
ftrace_64.S	x86/ibt,ftrace: Make function-graph play nice	2022-08-21 15:17:48 +02:00
ftrace.c	x86/ftrace: Use alternative RET encoding	2022-08-21 15:17:48 +02:00
head32.c
head64.c	x86: Clear .brk area at early boot	2022-07-21 21:24:40 +02:00
head_32.S	x86/asm/32: Fix ANNOTATE_UNRET_SAFE use on 32-bit	2022-07-23 12:54:12 +02:00
head_64.S	objtool: Add entry UNRET validation	2022-07-23 12:54:06 +02:00
hpet.c	rtc: Check return value from mc146818_get_time()	2022-04-13 20:59:14 +02:00
hw_breakpoint.c	x86/debug: Prevent data breakpoints on cpu_dr7	2021-02-05 20:13:12 +01:00
i8237.c
i8253.c
i8259.c	x86: Avoid magic number with ELCR register accesses	2021-08-10 23:31:43 +02:00
idt.c	X86 interrupt related changes:	2021-06-29 12:36:59 -07:00
io_delay.c
ioport.c
irq_32.c	softirq: Move do_softirq_own_stack() to generic asm header	2021-02-10 23:34:16 +01:00
irq_64.c	x86/softirq/64: Inline do_softirq_own_stack()	2021-02-10 23:34:17 +01:00
irq_work.c
irq.c	x86/irq: Ensure PI wakeup handler is unregistered before module unload	2021-11-18 19:15:56 +01:00
irqflags.S	x86: Prepare asm files for straight-line-speculation	2022-05-15 20:18:49 +02:00
irqinit.c	x86/headers: Remove APIC headers from <asm/smp.h>	2020-08-06 16:13:09 +02:00
itmt.c
jailhouse.c	locking/seqlock, headers: Untangle the spaghetti monster	2020-08-06 16:13:13 +02:00
jump_label.c	jump_labels: Mark __jump_label_transform() as __always_inlined to work around aggressive compiler un-inlining	2021-07-13 06:32:05 +02:00
kdebugfs.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-16 14:23:45 +01:00
kexec-bzimage64.c	x86: Use ELF fields defined in 'struct kimage'	2021-03-08 12:06:29 -07:00
kgdb.c	x86: Fix various typos in comments	2021-03-18 15:31:53 +01:00
ksysfs.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-16 14:23:45 +01:00
kvm.c	x86, kvm: use proper ASM macros for kvm_vcpu_is_preempted	2022-07-02 16:41:12 +02:00
kvmclock.c	x86/kvmclock: Move this_cpu_pvti into kvmclock.h	2021-09-30 04:08:01 -04:00
ldt.c	memcg: enable accounting for ldt_struct objects	2021-09-03 09:58:13 -07:00
machine_kexec_32.c	x86/kexec: Set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c	2021-05-21 12:36:45 +02:00
machine_kexec_64.c	x86/kexec: fix memory leak of elf header buffer	2022-06-09 10:22:29 +02:00
Makefile	x86/sev: Add an x86 version of cc_platform_has()	2021-11-18 19:17:21 +01:00
mmconf-fam10h_64.c	x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG	2021-05-10 07:51:38 +02:00
module.c	x86: Undo return-thunk damage	2022-07-23 12:53:58 +02:00
mpparse.c	x86: Avoid magic number with ELCR register accesses	2021-08-10 23:31:43 +02:00
msr.c	x86/MSR: Filter MSR writes through X86_IOC_WRMSR_REGS ioctl too	2021-01-27 19:06:47 +01:00
nmi_selftest.c
nmi.c	x86/sev-es: Rename sev-es.{ch} to sev.{ch}	2021-05-10 07:40:27 +02:00
paravirt-spinlocks.c	x86/paravirt: Add new features for paravirt patching	2021-03-11 19:51:49 +01:00
paravirt.c	x86: Prepare inline-asm for straight-line-speculation	2022-05-15 20:18:50 +02:00
pci-dma.c	dma-mapping: move dma-debug.h to kernel/dma/	2020-10-06 07:07:05 +02:00
pci-iommu_table.c	x86: Remove definition of DEBUG	2021-01-15 08:23:10 +01:00
pci-swiotlb.c
pcspeaker.c
perf_regs.c	- Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in the end	2020-12-14 13:45:26 -08:00
platform-quirks.c
pmem.c	x86/pmem: Fix platform-device leak in error path	2022-08-17 14:23:07 +02:00
probe_roms.c
process_32.c	x86/dumpstack: Add log_lvl to __show_regs()	2020-07-22 23:56:53 +02:00
process_64.c	x86/fpu: Add PKRU storage outside of task XSAVE buffer	2021-06-23 19:37:45 +02:00
process.c	x86: Handle idle=nomwait cmdline properly for x86_idle	2022-08-17 14:23:00 +02:00
process.h
ptrace.c	x86/ptrace: Fix xfpregs_set()'s incorrect xmm clearing	2022-03-02 11:47:47 +01:00
pvclock.c	x86: Fix various typos in comments	2021-03-18 15:31:53 +01:00
quirks.c	x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()	2020-10-06 11:18:04 +02:00
reboot_fixups_32.c
reboot.c	x86/mm: Flush global TLB when switching to trampoline page-table	2022-01-27 11:04:35 +01:00
relocate_kernel_32.S	x86/kexec: Disable RET on kexec	2022-07-23 12:54:11 +02:00
relocate_kernel_64.S	x86/kexec: Disable RET on kexec	2022-07-23 12:54:11 +02:00
resource.c
rtc.c
setup_percpu.c	memblock: introduce saner 'memblock_free_ptr()' interface	2021-09-14 13:23:22 -07:00
setup.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-16 14:23:45 +01:00
sev_verify_cbit.S	x86: Prepare asm files for straight-line-speculation	2022-05-15 20:18:49 +02:00
sev-shared.c	x86/sev: Return an error on a returned non-zero SW_EXITINFO1[31:0]	2021-10-01 11:14:41 +02:00
sev.c	x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword	2021-12-08 09:04:53 +01:00
signal_compat.c	signal: Deliver SIGTRAP on perf event asynchronously if blocked	2022-06-09 10:22:48 +02:00
signal.c	Fixes and improvements for FPU handling on x86:	2021-07-07 11:12:01 -07:00
smp.c	x86: Fix various typos in comments, take #2	2021-03-21 23:50:28 +01:00
smpboot.c	x86/smp: Add a per-cpu view of SMT state	2021-07-28 11:42:23 +02:00
stacktrace.c	stacktrace: Move documentation for arch_stack_walk_reliable() to header	2021-03-10 15:52:31 +01:00
static_call.c	x86/static_call: Serialize __static_call_fixup() properly	2022-07-23 12:54:11 +02:00
step.c	ptrace: Reimplement PTRACE_KILL by always sending SIGKILL	2022-06-09 10:22:29 +02:00
sys_ia32.c	x86: switch to kernel_clone()	2020-08-20 13:12:58 +02:00
sys_x86_64.c	x86/mm: Cleanup the control_va_addr_alignment() __setup handler	2022-06-09 10:22:54 +02:00
tboot.c	x86/boot/tboot: Avoid Wstringop-overread-warning	2021-03-23 00:16:13 +01:00
time.c
tls.c	x86/stackprotector/32: Make the canary into a regular percpu variable	2021-03-08 13:19:05 +01:00
tls.h	x86: switch to ->regset_get()	2020-07-27 14:31:07 -04:00
topology.c	x86: Fix various typos in comments	2021-03-18 15:31:53 +01:00
trace_clock.c
trace.c	trace/osnoise: Fix 'no previous prototype' warnings	2021-06-28 14:12:26 -04:00
tracepoint.c
traps.c	x86/traps: Use pt_regs directly in fixup_bad_iret()	2022-07-23 12:53:47 +02:00
tsc_msr.c	Misc fixes and small updates all around the place:	2020-08-15 10:38:03 -07:00
tsc_sync.c	x86/tsc: Add a timer to make sure TSC_adjust is always checked	2021-12-08 09:04:56 +01:00
tsc.c	x86/tsc: Disable clocksource watchdog for TSC on qualified platorms	2021-12-08 09:04:56 +01:00
umip.c	x86/insn: Extend error reporting from insn_fetch_from_user[_inatomic]()	2021-06-15 11:39:30 +02:00
unwind_frame.c	fork-v5.9	2020-08-04 14:47:45 -07:00
unwind_guess.c
unwind_orc.c	x86/unwind/orc: Fix unreliable stack dump with gcov	2022-11-03 23:59:16 +09:00
uprobes.c	x86/uprobes: Convert to insn_decode()	2021-03-15 12:05:03 +01:00
verify_cpu.S	x86: Prepare asm files for straight-line-speculation	2022-05-15 20:18:49 +02:00
vm86_32.c	signal: Replace force_fatal_sig with force_exit_sig when in doubt	2021-11-25 09:49:07 +01:00
vmlinux.lds.S	x86: Add magic AMD return-thunk	2022-07-23 12:54:01 +02:00
vsmp_64.c
x86_init.c	x86/apic: Support 15 bits of APIC ID in MSI where available	2020-10-28 20:26:29 +01:00