Commit-ID: aee4b013a71666f11ffeac11ab45bb7c6e0e394d Gitweb: http://git.kernel.org/tip/aee4b013a71666f11ffeac11ab45bb7c6e0e394d Author: Denys Vlasenko <dvlasenk@xxxxxxxxxx> AuthorDate: Tue, 9 Jun 2015 20:54:07 +0200 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Wed, 10 Jun 2015 08:42:12 +0200 x86/asm/entry/32: Fix fallout from the R9 trick removal in the SYSCALL code I put %ebp restoration code too late. Under strace, it is not reached and %ebp is not restored upon return to userspace. This is the fix. Run-tested. Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: Alexei Starovoitov <ast@xxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Will Drewry <wad@xxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1433876051-26604-1-git-send-email-dvlasenk@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/entry/entry_64_compat.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 2093ce6..2c44180 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -344,6 +344,7 @@ cstar_dispatch: call *ia32_sys_call_table(, %rax, 8) movq %rax, RAX(%rsp) 1: + movl RCX(%rsp), %ebp DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) @@ -351,7 +352,6 @@ cstar_dispatch: sysretl_from_sys_call: andl $~TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) - movl RCX(%rsp), %ebp RESTORE_RSI_RDI_RDX movl RIP(%rsp), %ecx movl EFLAGS(%rsp), %r11d -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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