Commit 87fb4b7b533073eeeaed0b6bf7c2328995f6c075 (net: more accurate skb truesize) changed the alignment of size. This can cause problems at least on some machines with NFS root: Unhandled fault: alignment exception (0x801) at 0xc183a43a Internal error: : 801 [#1] PREEMPT Modules linked in: CPU: 0 Not tainted (3.1.0-08784-g5eeee4a #733) pc : [<c02fbba0>] lr : [<c02fbb9c>] psr: 60000013 sp : c180fef8 ip : 00000000 fp : c181f580 r10: 00000000 r9 : c044b28c r8 : 00000001 r7 : c183a3a0 r6 : c1835be0 r5 : c183a412 r4 : 000001f2 r3 : 00000000 r2 : 00000000 r1 : ffffffe6 r0 : c183a43a Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 0005317f Table: 10004000 DAC: 00000017 Process swapper (pid: 1, stack limit = 0xc180e270) Stack: (0xc180fef8 to 0xc1810000) fee0: 00000024 00000000 ff00: 00000000 c183b9c0 c183b8e0 c044b28c c0507ccc c019dfc4 c180ff2c c0503cf8 ff20: c180ff4c c180ff4c 00000000 c1835420 c182c740 c18349c0 c05233c0 00000000 ff40: 00000000 c00e6bb8 c180e000 00000000 c04dd82c c0507e7c c050cc18 c183b9c0 ff60: c05233c0 00000000 00000000 c01f34f4 c0430d70 c019d364 c04dd898 c04dd898 ff80: c04dd82c c0507e7c c180e000 00000000 c04c584c c01f4918 c04dd898 c04dd82c ffa0: c04ddd28 c180e000 00000000 c0008758 c181fa60 3231d82c 00000037 00000000 ffc0: 00000000 c04dd898 c04dd82c c04ddd28 00000013 00000000 00000000 00000000 ffe0: 00000000 c04b2224 00000000 c04b21a0 c001056c c001056c 00000000 00000000 Function entered at [<c02fbba0>] from [<c019dfc4>] Function entered at [<c019dfc4>] from [<c01f34f4>] Function entered at [<c01f34f4>] from [<c01f4918>] Function entered at [<c01f4918>] from [<c0008758>] Function entered at [<c0008758>] from [<c04b2224>] Function entered at [<c04b2224>] from [<c001056c>] Code: e1a00005 e3a01028 ebfa7cb0 e35a0000 (e5858028) Here PC is at __alloc_skb and &shinfo->dataref is unaligned because skb->end can be unaligned without this patch. Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -189,6 +189,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, * aligned memory blocks, unless SLUB/SLAB debug is enabled. * Both skb->head and skb_shared_info are cache line aligned. */ + size = SKB_DATA_ALIGN(size); size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); data = kmalloc_node_track_caller(size, gfp_mask, node); if (!data) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
