linux/arch/sparc
David S. Miller 84bd6d8b9c sparc64: Fix corrupted thread fault code.
Every path that ends up at do_sparc64_fault() must install a valid
FAULT_CODE_* bitmask in the per-thread fault code byte.

Two paths leading to the label winfix_trampoline (which expects the
FAULT_CODE_* mask in register %g4) were not doing so:

1) For pre-hypervisor TLB protection violation traps, if we took
   the 'winfix_trampoline' path we wouldn't have %g4 initialized
   with the FAULT_CODE_* value yet.  Resulting in using the
   TLB_TAG_ACCESS register address value instead.

2) In the TSB miss path, when we notice that we are going to use a
   hugepage mapping, but we haven't allocated the hugepage TSB yet, we
   still have to take the window fixup case into consideration and
   in that particular path we leave %g4 not setup properly.

Errors on this sort were largely invisible previously, but after
commit 4ccb927289 ("sparc64: sun4v TLB
error power off events") we now have a fault_code mask bit
(FAULT_CODE_BAD_RA) that triggers due to this bug.

FAULT_CODE_BAD_RA triggers because this bit is set in TLB_TAG_ACCESS
(see #1 above) and thus we get seemingly random bus errors triggered
for user processes.

Fixes: 4ccb927289 ("sparc64: sun4v TLB error power off events")
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-18 23:03:09 -04:00
..
boot sparc: Add "install" target 2014-08-04 20:45:59 -07:00
configs sparc: Set CONFIG_NET=y in defconfigs 2014-09-24 13:38:30 -04:00
crypto sparc64: fix sparse warnings in aes_glue.c 2014-05-18 19:01:33 -07:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2014-10-18 09:30:41 -07:00
kernel sparc64: Fix corrupted thread fault code. 2014-10-18 23:03:09 -04:00
lib sparc64: Fix FPU register corruption with AES crypto offload. 2014-10-14 19:37:58 -07:00
math-emu arch/sparc/math-emu/math_32.c: drop stray break operator 2014-08-04 20:29:06 -07:00
mm Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2014-10-15 07:48:18 +02:00
net sparc: bpf_jit: add support for BPF_LD(X) | BPF_LEN instructions 2014-09-26 16:52:09 -04:00
oprofile sparc: using HZ needs an include of linux/param.h 2009-10-05 00:46:08 -07:00
power Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2014-10-11 20:36:34 -04:00
prom sparc64: Fix lockdep warnings on reboot on Ultra-5 2014-10-10 15:49:16 -04:00
Kbuild sparc64: Add SHA1 driver making use of the 'sha1' instruction. 2012-08-20 15:08:49 -07:00
Kconfig sparc64: sparse irq 2014-10-05 16:53:40 -07:00
Kconfig.debug lib: consolidate DEBUG_STACK_USAGE option 2011-05-25 08:39:54 -07:00
Makefile sparc: Add "install" target 2014-08-04 20:45:59 -07:00