> I've hit the following oops on boot on an XO-1 with current linus git: > > [ 0.662755] BUG: unable to handle kernel NULL pointer dereference at 00000024 > [ 0.666349] IP: [<c11a0514>] apei_hest_parse+0xbc/0xcc > [ 0.666349] *pde = 00000000 > [ 0.666349] Oops: 0000 [#1] SMP > [ 0.666349] last sysfs file: > [ 0.666349] Modules linked in: > [ 0.666349] > [ 0.666349] Pid: 1, comm: swapper Not tainted 2.6.37+ #74 / > [ 0.666349] EIP: 0060:[<c11a0514>] EFLAGS: 00010206 CPU: 0 > [ 0.666349] EIP is at apei_hest_parse+0xbc/0xcc > [ 0.666349] EAX: 00000028 EBX: 00000000 ECX: 00000000 EDX: 00000000 > [ 0.666349] ESI: 00000001 EDI: 00000000 EBP: c1161171 ESP: cb441fa8 > [ 0.666349] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 > [ 0.666349] Process swapper (pid: 1, ti=cb440000 task=cb43c000 task.ti=cb440000) > [ 0.666349] Stack: > [ 0.666349] c1450960 00000001 00000020 c141fa10 c11611aa c141fa1e c1001151 00000000 > [ 0.666349] c1450960 00000001 00000020 00000000 c1401346 00000000 c1401221 00000000 > [ 0.666349] c10034be 00000000 00000000 00000000 00000000 00000000 > [ 0.666349] Call Trace: > [ 0.666349] [<c141fa10>] ? aer_service_init+0x0/0x22 > [ 0.666349] [<c11611aa>] ? aer_acpi_firmware_first+0x15/0x22 > [ 0.666349] [<c141fa1e>] ? aer_service_init+0xe/0x22 > [ 0.666349] [<c1001151>] ? do_one_initcall+0x68/0x10f > [ 0.666349] [<c1401346>] ? kernel_init+0x125/0x19d > [ 0.666349] [<c1401221>] ? kernel_init+0x0/0x19d > [ 0.666349] [<c10034be>] ? kernel_thread_helper+0x6/0x10 > [ 0.666349] Code: 76 18 0f b7 40 02 50 68 c2 ae 35 c1 e8 3e e8 0f 00 b8 ea ff ff ff 59 5b eb 1c 89 fa ff d5 85 c0 75 14 89 f0 43 8b 0d 50 ed 3f c1 <3b> 59 > 24 0f 82 64 ff ff ff 31 c0 5b 5e 5f 5d c3 8b 50 0c 8d 4a > > The apei_hest_parse function is using hest_tab, which hasn't been initialized. > This is because acpi_hest_init has never been called (as acpi_pci_disabled is 1, > so it never gets called from acpi_pci_root_init), and hest_disabled is never > set to 1. When the aer_driver calls apei_hest_parse, the hest_disabled check > passes, and it oopses processing hest_tab. Note that the aer code that > calls apei_hest_parse was added in commit b22c3d82. > > This patch causes apei_hest_parse to check both hest_disabled and > acpi_pci_disabled before continuing. With it, the XO-1 boots properly. The X0-1 has no ACPI support, and thus you are running with acpi_disabled=1, yes? It would be better for the fix to depend on acpi_disabled. acpi_disbled=1 is a supported configuration, while acpi_pci_disabled is a just a debug flag, maybe someday it will go away. Looks like acpi_hest_init() bails for acpi_disabled, and thus hest_ghes_dev_register()doens't run and invoke apei_hest_parse(), so we are set there. Seems like drivers/pci/pcie/aer/aerdrv_acpi.c, should not invoke apei_hest_parse() when acpi_disabled=1. Either that or we have to have apei_hest_parse(), which is exported to modules check acpi_disabled -- and its callers need to check for failure. thanks, -Len Brown, Intel Open Source Technolgy Center > Signed-off-by: Andres Salomon <dilinger@xxxxxxxxxx> > --- > drivers/acpi/apei/hest.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c > index 4ee58e7..2b8c355 100644 > --- a/drivers/acpi/apei/hest.c > +++ b/drivers/acpi/apei/hest.c > @@ -89,7 +89,7 @@ int apei_hest_parse(apei_hest_func_t func, void *data) > struct acpi_hest_header *hest_hdr; > int i, rc, len; > > - if (hest_disable) > + if (hest_disable || acpi_pci_disabled) > return -EINVAL; > > hest_hdr = (struct acpi_hest_header *)(hest_tab + 1); > -- > 1.7.2.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
