Ingo Molnar wrote: > FYI, -tip testing has triggered this new crash in dev_attr_show() et al: > > [ 158.058140] warning: `dbus-daemon' uses 32-bit capabilities (legacy support in use) > [ 159.370562] BUG: unable to handle kernel NULL pointer dereference at (null) > [ 159.372694] IP: [<ffffffff8143b722>] bitmap_scnprintf+0x72/0xd0 > [ 159.372694] PGD 71d3e067 PUD 7052e067 PMD 0 > [ 159.372694] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC > [ 159.372694] last sysfs file: /sys/devices/pci0000:00/0000:00:01.0/local_cpus > [ 159.372694] CPU 0 > [ 159.372694] Pid: 7364, comm: irqbalance Not tainted 2.6.31-tip #8043 System Product Name > [ 159.372694] RIP: 0010:[<ffffffff8143b722>] [<ffffffff8143b722>] bitmap_scnprintf+0x72/0xd0 > [ 159.372694] RSP: 0018:ffff8800712a1e38 EFLAGS: 00010246 > [ 159.372694] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 > [ 159.372694] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff880077dc5000 > [ 159.372694] RBP: ffff8800712a1e68 R08: 0000000000000001 R09: 0000000000000001 > [ 159.372694] R10: ffffffff8215c47c R11: 0000000000000000 R12: 0000000000000000 > [ 159.372694] R13: 0000000000000000 R14: 0000000000000ffe R15: ffff880077dc5000 > [ 159.372694] FS: 00007f5f578f76f0(0000) GS:ffff880007000000(0000) knlGS:0000000000000000 > [ 159.372694] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > [ 159.372694] CR2: 0000000000000000 CR3: 0000000071a77000 CR4: 00000000000006f0 > [ 159.372694] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 159.372694] DR3: ffffffff835109dc DR6: 00000000ffff0ff0 DR7: 0000000000000400 > [ 159.372694] Process irqbalance (pid: 7364, threadinfo ffff8800712a0000, task ffff880070773000) > [ 159.372694] Stack: > [ 159.372694] 2222222222222222 ffff880077dc5000 fffffffffffffffb ffff88007d366b40 > [ 159.372694] <0> ffff8800712a1f48 ffff88007d3840a0 ffff8800712a1e88 ffffffff8146332b > [ 159.372694] <0> fffffffffffffff4 ffffffff82450718 ffff8800712a1ea8 ffffffff815a9a1f > [ 159.372694] Call Trace: > [ 159.372694] [<ffffffff8146332b>] local_cpus_show+0x3b/0x60 > [ 159.372694] [<ffffffff815a9a1f>] dev_attr_show+0x2f/0x60 > [ 159.372694] [<ffffffff8118ee6f>] sysfs_read_file+0xbf/0x1d0 > [ 159.372694] [<ffffffff8112afe9>] vfs_read+0xc9/0x180 > [ 159.372694] [<ffffffff8112c365>] sys_read+0x55/0x90 > [ 159.372694] [<ffffffff810114f2>] system_call_fastpath+0x16/0x1b > [ 159.372694] Code: 41 b9 01 00 00 00 44 8d 46 03 49 63 fc 0f 49 d3 c1 f8 1f 4c 01 ff c1 e8 1a c1 fa 06 41 c1 e8 02 8d 0c 03 48 63 d2 83 e1 3f 29 c1 <49> 8b 44 d5 00 48 c7 c2 8c 37 16 82 48 d3 e8 89 f1 44 89 f6 49 > [ 159.372694] RIP [<ffffffff8143b722>] bitmap_scnprintf+0x72/0xd0 > [ 159.372694] RSP <ffff8800712a1e38> > [ 159.372694] CR2: 0000000000000000 > [ 159.600828] ---[ end trace 35550c356e84e60c ]--- > > That's a new breakage as well. Config and full crashlog attached. > exposed by Jesse's patch too. please check --- arch/x86/include/asm/pci.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) Index: linux-2.6/arch/x86/include/asm/pci.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/pci.h +++ linux-2.6/arch/x86/include/asm/pci.h @@ -143,7 +143,14 @@ static inline int __pcibus_to_node(const static inline const struct cpumask * cpumask_of_pcibus(const struct pci_bus *bus) { - return cpumask_of_node(__pcibus_to_node(bus)); + int node; + + node = __pcibus_to_node(bus); + + if (node == -1) + node = numa_node_id(); + + return cpumask_of_node(node); } #endif -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html