Commit-ID: 0784b36448a2a85b95b6eb21a69b9045c896c065 Gitweb: http://git.kernel.org/tip/0784b36448a2a85b95b6eb21a69b9045c896c065 Author: Denys Vlasenko <[email protected]> AuthorDate: Wed, 1 Apr 2015 16:50:57 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 2 Apr 2015 12:00:10 +0200
x86/asm/entry/64: Fold the 'test_in_nmi' macro into its only user No code changes. Signed-off-by: Denys Vlasenko <[email protected]> Acked-by: Borislav Petkov <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Kees Cook <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Will Drewry <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/entry_64.S | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 03c52e2..386375d 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1355,19 +1355,7 @@ ENTRY(error_exit) CFI_ENDPROC END(error_exit) -/* - * Test if a given stack is an NMI stack or not. - */ - .macro test_in_nmi reg stack nmi_ret normal_ret - cmpq %\reg, \stack - ja \normal_ret - subq $EXCEPTION_STKSZ, %\reg - cmpq %\reg, \stack - jb \normal_ret - jmp \nmi_ret - .endm - - /* runs on exception stack */ +/* Runs on exception stack */ ENTRY(nmi) INTR_FRAME PARAVIRT_ADJUST_EXCEPTION_FRAME @@ -1428,8 +1416,18 @@ ENTRY(nmi) * We check the variable because the first NMI could be in a * breakpoint routine using a breakpoint stack. */ - lea 6*8(%rsp), %rdx - test_in_nmi rdx, 4*8(%rsp), nested_nmi, first_nmi + lea 6*8(%rsp), %rdx + /* Compare the NMI stack (rdx) with the stack we came from (4*8(%rsp)) */ + cmpq %rdx, 4*8(%rsp) + /* If the stack pointer is above the NMI stack, this is a normal NMI */ + ja first_nmi + subq $EXCEPTION_STKSZ, %rdx + cmpq %rdx, 4*8(%rsp) + /* If it is below the NMI stack, it is a normal NMI */ + jb first_nmi + /* Ah, it is within the NMI stack, treat it as nested */ + jmp nested_nmi + CFI_REMEMBER_STATE nested_nmi: -- 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/
