Commit-ID: 3bd29515d1cad26fa85a1a9b442de8816c1f5c54 Gitweb: http://git.kernel.org/tip/3bd29515d1cad26fa85a1a9b442de8816c1f5c54 Author: Andy Lutomirski <[email protected]> AuthorDate: Fri, 16 Oct 2015 15:42:55 -0700 Committer: Ingo Molnar <[email protected]> CommitDate: Sun, 18 Oct 2015 12:11:16 +0200
x86/entry/32: Fix FS and GS restore in opportunistic SYSEXIT We either need to restore them before popping and thus changing ESP, or we need to adjust the offsets. The former is simpler. Reported-and-tested-by: Borislav Petkov <[email protected]> Signed-off-by: Andy Lutomirski <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Fixes: 5f310f739b4c x86/entry/32: ("Re-implement SYSENTER using the new C path") Link: http://lkml.kernel.org/r/461e5c7d8fa3821529893a4893ac9c4bc37f9e17.1445035014.git.l...@kernel.org Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/entry/entry_32.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 4f97f49..3eb572e 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -315,14 +315,14 @@ sysenter_past_esp: TRACE_IRQS_ON /* User mode traces as IRQs on. */ movl PT_EIP(%esp), %edx /* pt_regs->ip */ movl PT_OLDESP(%esp), %ecx /* pt_regs->sp */ +1: mov PT_FS(%esp), %fs + PTGS_TO_GS popl %ebx /* pt_regs->bx */ addl $2*4, %esp /* skip pt_regs->cx and pt_regs->dx */ popl %esi /* pt_regs->si */ popl %edi /* pt_regs->di */ popl %ebp /* pt_regs->bp */ popl %eax /* pt_regs->ax */ -1: mov PT_FS(%esp), %fs - PTGS_TO_GS /* * Return back to the vDSO, which will pop ecx and edx. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
