From: Narayan Newton <nnewton@xxxxxxxxxx> Date: Mon, 12 Mar 2007 16:58:56 -0700 > I have been working on the same server/issue as Mike. We have found that > our kernel without Netfilter support does not have this issue, but the > moment you enable it in the kernel config this bug is triggered. > Attached are the two kernel configs. The only difference is > CONFIG_NETFILTER=y > > Kernel version: 2.6.21-rc2 Ok, I think the following patch is the bug fix. I'm running a bunch of further stress testing to make sure this is indeed the cause of these crashes. Let me know if you can still trigger the bug with this patch applied, thanks! Assuming all goes well I'll push this upstream to Linus and also to the -stable 2.6.x branches. [SPARC64]: store-init needs trailing membar. The manual says that it is required and we actually have crash reports where loads see stale data due to not having membars here. In one case the networking does: memset(skb, 0, offsetof(struct sk_buff, truesize)); and then some code later checks skb->nohdr for zero, but it's still the value that was there before the memset(). Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> diff --git a/arch/sparc64/lib/NGbzero.S b/arch/sparc64/lib/NGbzero.S index e86baec..f10e452 100644 --- a/arch/sparc64/lib/NGbzero.S +++ b/arch/sparc64/lib/NGbzero.S @@ -88,6 +88,7 @@ NGbzero_loop: bne,pt %xcc, NGbzero_loop add %o0, 64, %o0 + membar #Sync wr %o4, 0x0, %asi brz,pn %o1, NGbzero_done NGbzero_medium: diff --git a/arch/sparc64/lib/NGmemcpy.S b/arch/sparc64/lib/NGmemcpy.S index 8e522b3..66063a9 100644 --- a/arch/sparc64/lib/NGmemcpy.S +++ b/arch/sparc64/lib/NGmemcpy.S @@ -247,6 +247,8 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */ /* fall through */ 60: + membar #Sync + /* %o2 contains any final bytes still needed to be copied * over. If anything is left, we copy it one byte at a time. */ diff --git a/arch/sparc64/lib/NGpage.S b/arch/sparc64/lib/NGpage.S index 7d7c3bb..8ce3a0c 100644 --- a/arch/sparc64/lib/NGpage.S +++ b/arch/sparc64/lib/NGpage.S @@ -41,6 +41,7 @@ NGcopy_user_page: /* %o0=dest, %o1=src, %o2=vaddr */ subcc %g7, 64, %g7 bne,pt %xcc, 1b add %o0, 32, %o0 + membar #Sync retl nop @@ -63,6 +64,7 @@ NGclear_user_page: /* %o0=dest, %o1=vaddr */ subcc %g7, 64, %g7 bne,pt %xcc, 1b add %o0, 32, %o0 + membar #Sync retl nop - To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
