Commit-ID: 9d0c914c60f4d3123debb653340dc1f7cf44939d Gitweb: http://git.kernel.org/tip/9d0c914c60f4d3123debb653340dc1f7cf44939d Author: Andy Lutomirski <luto@xxxxxxxxxxxxxx> AuthorDate: Thu, 5 Mar 2015 19:19:04 -0800 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 6 Mar 2015 08:32:58 +0100 x86/asm/entry/64/compat: Change the 32-bit sysenter code to use sp0 The ia32 sysenter code loaded the top of the kernel stack into rsp by loading kernel_stack and then adjusting it. It can be simplified to just read sp0 directly. This requires the addition of a new asm-offsets entry for sp0. Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/88ff9006163d296a0665338585c36d9bfb85235d.1425611534.git.luto@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/ia32/ia32entry.S | 3 +-- arch/x86/kernel/asm-offsets_64.c | 1 + 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index ed97463..719db63 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -113,8 +113,7 @@ ENTRY(ia32_sysenter_target) CFI_DEF_CFA rsp,0 CFI_REGISTER rsp,rbp SWAPGS_UNSAFE_STACK - movq PER_CPU_VAR(kernel_stack), %rsp - addq $(KERNEL_STACK_OFFSET),%rsp + movq PER_CPU_VAR(init_tss + TSS_sp0), %rsp /* * No need to follow this irqs on/off section: the syscall * disabled irqs, here we enable it straight after entry: diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index fdcbb4d..5ce6f2d 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -81,6 +81,7 @@ int main(void) #undef ENTRY OFFSET(TSS_ist, tss_struct, x86_tss.ist); + OFFSET(TSS_sp0, tss_struct, x86_tss.sp0); BLANK(); DEFINE(__NR_syscall_max, sizeof(syscalls_64) - 1); -- 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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