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author | Andy Lutomirski <luto@amacapital.net> | 2015-03-06 06:19:04 +0300 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2015-03-06 10:32:58 +0300 |
commit | 9d0c914c60f4d3123debb653340dc1f7cf44939d (patch) | |
tree | 41cd00a5332551608057bd6a08d1724a081971f5 /arch/x86/ia32 | |
parent | 75182b1632a89f12540baa1806a7c5c180db620c (diff) | |
download | linux-9d0c914c60f4d3123debb653340dc1f7cf44939d.tar.xz |
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@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/88ff9006163d296a0665338585c36d9bfb85235d.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/ia32')
-rw-r--r-- | arch/x86/ia32/ia32entry.S | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index ed9746340363..719db63b35c4 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: |