[PATCH] x86_64: fix iret exception recovery
This change broke recovery of exceptions in iret: commit 72fe4858544292ad64600765cb78bc02298c6b1c Author: Glauber de Oliveira Costa <[EMAIL PROTECTED]> x86: replace privileged instructions with paravirt macros The ENTRY(native_iret) macro adds alignment padding before the iretq instruction, so "iret_label" no longer points exactly at the instruction. It was sloppy to leave the old "iret_label" label behind when replacing its nearby use. Removing it would have revealed the other use of the label later in the file, and upon noticing that use, anyone exercising the minimum of attention to detail expected of anyone touching this subtle code would realize it needed to change as well. Signed-off-by: Roland McGrath <[EMAIL PROTECTED]> --- arch/x86/kernel/entry_64.S |3 +-- 1 files changed, 1 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index bea8474..07d4aba 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -582,7 +582,6 @@ retint_restore_args:/* return to kernel space */ TRACE_IRQS_IRETQ restore_args: RESTORE_ARGS 0,8,0 -iret_label: #ifdef CONFIG_PARAVIRT INTERRUPT_RETURN #endif @@ -911,7 +910,7 @@ error_kernelspace: iret run with kernel gs again, so don't set the user space flag. B stepping K8s sometimes report an truncated RIP for IRET exceptions returning to compat mode. Check for these here too. */ - leaq iret_label(%rip),%rbp + leaq native_iret(%rip),%rbp cmpq %rbp,RIP(%rsp) je error_swapgs movl %ebp,%ebp /* zero extend */ -- 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/
[PATCH] x86_64: fix iret exception recovery
This change broke recovery of exceptions in iret: commit 72fe4858544292ad64600765cb78bc02298c6b1c Author: Glauber de Oliveira Costa [EMAIL PROTECTED] x86: replace privileged instructions with paravirt macros The ENTRY(native_iret) macro adds alignment padding before the iretq instruction, so iret_label no longer points exactly at the instruction. It was sloppy to leave the old iret_label label behind when replacing its nearby use. Removing it would have revealed the other use of the label later in the file, and upon noticing that use, anyone exercising the minimum of attention to detail expected of anyone touching this subtle code would realize it needed to change as well. Signed-off-by: Roland McGrath [EMAIL PROTECTED] --- arch/x86/kernel/entry_64.S |3 +-- 1 files changed, 1 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index bea8474..07d4aba 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -582,7 +582,6 @@ retint_restore_args:/* return to kernel space */ TRACE_IRQS_IRETQ restore_args: RESTORE_ARGS 0,8,0 -iret_label: #ifdef CONFIG_PARAVIRT INTERRUPT_RETURN #endif @@ -911,7 +910,7 @@ error_kernelspace: iret run with kernel gs again, so don't set the user space flag. B stepping K8s sometimes report an truncated RIP for IRET exceptions returning to compat mode. Check for these here too. */ - leaq iret_label(%rip),%rbp + leaq native_iret(%rip),%rbp cmpq %rbp,RIP(%rsp) je error_swapgs movl %ebp,%ebp /* zero extend */ -- 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/
