diff options
| author | Hari Bathini <hbathini@linux.vnet.ibm.com> | 2014-10-01 12:32:30 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2014-10-30 16:52:46 +1100 |
| commit | 408cddd96e3b155337f9e3aba2198e92e94c6068 (patch) | |
| tree | 6000ae44112cace02d07c253a6b867aaea7b038b /arch/powerpc/platforms | |
| parent | 94966b712c6875939fcdd83cb2707a797e131a43 (diff) | |
powerpc/fadump: Fix endianess issues in firmware assisted dump handling
Firmware-assisted dump (fadump) kernel code is not endian safe. The
below patch fixes this issue. Tested this patch with upstream kernel.
Below output shows crash tool successfully opening LE fadump vmcore.
# crash vmlinux vmcore
GNU gdb (GDB) 7.6
This GDB was configured as "powerpc64le-unknown-linux-gnu"...
KERNEL: vmlinux
DUMPFILE: vmcore
CPUS: 16
DATE: Wed Dec 31 19:00:00 1969
UPTIME: 00:03:28
LOAD AVERAGE: 0.46, 0.86, 0.41
TASKS: 268
NODENAME: linux-dhr2
RELEASE: 3.17.0-rc5-7-default
VERSION: #6 SMP Tue Sep 30 01:06:34 EDT 2014
MACHINE: ppc64le (4116 Mhz)
MEMORY: 40 GB
PANIC: "Oops: Kernel access of bad area, sig: 11 [#1]" (check log for details)
PID: 6223
COMMAND: "bash"
TASK: c0000009661b2500 [THREAD_INFO: c000000967ac0000]
CPU: 2
STATE: TASK_RUNNING (PANIC)
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
[mpe: Make the comment in pSeries_lpar_hptab_clear() clearer]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/pseries/lpar.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 8c509d5397c6..f6880d2a40fb 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -43,6 +43,7 @@ #include <asm/trace.h> #include <asm/firmware.h> #include <asm/plpar_wrappers.h> +#include <asm/fadump.h> #include "pseries.h" @@ -247,8 +248,17 @@ static void pSeries_lpar_hptab_clear(void) } #ifdef __LITTLE_ENDIAN__ - /* Reset exceptions to big endian */ - if (firmware_has_feature(FW_FEATURE_SET_MODE)) { + /* + * Reset exceptions to big endian. + * + * FIXME this is a hack for kexec, we need to reset the exception + * endian before starting the new kernel and this is a convenient place + * to do it. + * + * This is also called on boot when a fadump happens. In that case we + * must not change the exception endian mode. + */ + if (firmware_has_feature(FW_FEATURE_SET_MODE) && !is_fadump_active()) { long rc; rc = pseries_big_endian_exceptions(); |