Only fair: I touched this code a few times recently while
re-enabling KGDB support, but I didn't noticed this lethal bug. Now I
had to hunt it for half a day.

What was wrong should be obvious. Its effect was a spuriously unstalled
root domain once in a while after we handled a fault over a non-root
domain. Fortunately this is a corner case - unless you use the FPU in
userspace (initial usage fault...).

Patch is (still) against 2.6.26, but it is required for all recent
i386/x86_64/x86 ipipe versions, from 2.6.23 to 2.6.27.

Signed-off-by: Jan Kiszka <[EMAIL PROTECTED]>
---
 arch/x86/kernel/ipipe.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Index: b/arch/x86/kernel/ipipe.c
===================================================================
--- a/arch/x86/kernel/ipipe.c
+++ b/arch/x86/kernel/ipipe.c
@@ -751,7 +751,7 @@ int __ipipe_handle_exception(struct pt_r
        if (!ipipe_root_domain_p &&
            __ipipe_xlate_signo[vector] >= 0 &&
            !kgdb_handle_exception(vector, __ipipe_xlate_signo[vector], 
error_code, regs)) {
-               if (!flags)
+               if (flags & X86_EFLAGS_IF)
                        __clear_bit(IPIPE_STALL_FLAG,
                                    &ipipe_root_cpudom_var(status));
                return 1;
@@ -759,7 +759,7 @@ int __ipipe_handle_exception(struct pt_r
 #endif /* CONFIG_KGDB */
 
        if (unlikely(ipipe_trap_notify(vector, regs))) {
-               if (!flags)
+               if (flags & X86_EFLAGS_IF)
                        __clear_bit(IPIPE_STALL_FLAG,
                                    &ipipe_root_cpudom_var(status));
                return 1;

Attachment: signature.asc
Description: OpenPGP digital signature

_______________________________________________
Adeos-main mailing list
[email protected]
https://mail.gna.org/listinfo/adeos-main

Reply via email to