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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-04-30 11:44:18 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-04-30 11:44:18 -0700 |
| commit | 97ce89f8a4eb15a1e82be419fcd6218fe4da1fbd (patch) | |
| tree | 9860f04d4ddbb527d068493c233d2a2ed373b1e9 /arch/x86/kernel | |
| parent | 14e07f023ff6ed3e38850a9935a05b0b8e52fa49 (diff) | |
| parent | 88d879d29f9cc0de2d930b584285638cdada6625 (diff) | |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"The final fixes for 4.11:
- prevent a triple fault with function graph tracing triggered via
suspend to ram
- prevent optimizing for size when function graph tracing is enabled
and the compiler does not support -mfentry
- prevent mwaitx() being called with a zero timeout as mwaitx() might
never return. Observed on the new Ryzen CPUs"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Prevent timer value 0 for MWAITX
x86/build: convert function graph '-Os' error to warning
ftrace/x86: Fix triple fault with graph tracing and suspend-to-ram
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index cbd73eb42170..5b7153540727 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -29,12 +29,6 @@ #include <asm/ftrace.h> #include <asm/nops.h> -#if defined(CONFIG_FUNCTION_GRAPH_TRACER) && \ - !defined(CC_USING_FENTRY) && \ - !defined(CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE) -# error The following combination is not supported: ((compiler missing -mfentry) || (CONFIG_X86_32 and !CONFIG_DYNAMIC_FTRACE)) && CONFIG_FUNCTION_GRAPH_TRACER && CONFIG_CC_OPTIMIZE_FOR_SIZE -#endif - #ifdef CONFIG_DYNAMIC_FTRACE int ftrace_arch_code_modify_prepare(void) @@ -989,6 +983,18 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, unsigned long return_hooker = (unsigned long) &return_to_handler; + /* + * When resuming from suspend-to-ram, this function can be indirectly + * called from early CPU startup code while the CPU is in real mode, + * which would fail miserably. Make sure the stack pointer is a + * virtual address. + * + * This check isn't as accurate as virt_addr_valid(), but it should be + * good enough for this purpose, and it's fast. + */ + if (unlikely((long)__builtin_frame_address(0) >= 0)) + return; + if (unlikely(ftrace_graph_is_dead())) return; |