diff options
| author | Aaron Campbell <aaron@cvs.openbsd.org> | 2005-12-13 16:14:50 +0000 |
|---|---|---|
| committer | Aaron Campbell <aaron@cvs.openbsd.org> | 2005-12-13 16:14:50 +0000 |
| commit | d7cd8f61d3b2e4c6c3cbb6117d86eb2ccd14414f (patch) | |
| tree | 8c3178cc33a99c728931246b143d11729b47dc08 /sys/arch/i386/isa | |
| parent | 8e751e82340662a34e4ded0556545dc6c66cf284 (diff) | |
Prevent recursive interrupts. Solves kernel stack overflow on i386 under
heavy network interrupt load (I can reproduce with an ARP flood) with an MP
kernel. Patch from NetBSD PR20180.
Has been in snapshots for a bit. Testing by pedro@, jolan@. deraadt@ ok
Diffstat (limited to 'sys/arch/i386/isa')
| -rw-r--r-- | sys/arch/i386/isa/icu.s | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/sys/arch/i386/isa/icu.s b/sys/arch/i386/isa/icu.s index ed415f31fd7..743c2dc7c21 100644 --- a/sys/arch/i386/isa/icu.s +++ b/sys/arch/i386/isa/icu.s @@ -1,4 +1,4 @@ -/* $OpenBSD: icu.s,v 1.22 2005/01/07 02:03:17 pascoe Exp $ */ +/* $OpenBSD: icu.s,v 1.23 2005/12/13 16:14:49 aaron Exp $ */ /* $NetBSD: icu.s,v 1.45 1996/01/07 03:59:34 mycroft Exp $ */ /*- @@ -59,13 +59,17 @@ IDTVEC(spllower) 1: movl %ebx,%eax # get cpl shrl $4,%eax # find its mask. movl _C_LABEL(iunmask)(,%eax,4),%eax + cli andl _C_LABEL(ipending),%eax # any non-masked bits left? jz 2f + sti bsfl %eax,%eax btrl %eax,_C_LABEL(ipending) jnc 1b jmp *_C_LABEL(Xrecurse)(,%eax,4) -2: popl %edi +2: movl %ebx,CPL + sti + popl %edi popl %esi popl %ebx ret @@ -80,13 +84,14 @@ IDTVEC(spllower) */ IDTVEC(doreti) popl %ebx # get previous priority - movl %ebx,CPL movl $1f,%esi # address to resume loop at 1: movl %ebx,%eax shrl $4,%eax movl _C_LABEL(iunmask)(,%eax,4),%eax + cli andl _C_LABEL(ipending),%eax jz 2f + sti bsfl %eax,%eax # slow, but not worth optimizing btrl %eax,_C_LABEL(ipending) jnc 1b # some intr cleared the in-memory bit @@ -94,7 +99,7 @@ IDTVEC(doreti) jmp *_C_LABEL(Xresume)(,%eax,4) 2: /* Check for ASTs on exit to user mode. */ CHECK_ASTPENDING(%ecx) - cli + movl %ebx,CPL je 3f testb $SEL_RPL,TF_CS(%esp) #ifdef VM86 @@ -130,7 +135,6 @@ IDTVEC(softtty) #ifdef MULTIPROCESSOR call _C_LABEL(i386_softintunlock) #endif - movl %ebx,CPL #endif jmp *%esi @@ -154,7 +158,6 @@ IDTVEC(softnet) #ifdef MULTIPROCESSOR call _C_LABEL(i386_softintunlock) #endif - movl %ebx,CPL jmp *%esi #undef DONETISR @@ -169,6 +172,5 @@ IDTVEC(softclock) #ifdef MULTIPROCESSOR call _C_LABEL(i386_softintunlock) #endif - movl %ebx,CPL jmp *%esi |