diff options
| author | James Yang <James.Yang@freescale.com> | 2013-06-25 11:41:05 -0500 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-06-30 15:49:40 +1000 |
| commit | 80aa0fb4940bf8ee52bcb574d74459a7aea45621 (patch) | |
| tree | 6b110dea572ce2a63e4cd47bf95ede1e9a8b2ee4 /arch/powerpc | |
| parent | e1b85c17bf3e4f2ecbf9ec824c4048a06078100b (diff) | |
powerpc: Fix string instr. emulation for 32-bit processes on ppc64
String instruction emulation would erroneously result in a segfault if
the upper bits of the EA are set and is so high that it fails access
check. Truncate the EA to 32 bits if the process is 32-bit.
Signed-off-by: James Yang <James.Yang@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 071f6e040eb..300daf3e7ab 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -866,6 +866,10 @@ static int emulate_string_inst(struct pt_regs *regs, u32 instword) u8 val; u32 shift = 8 * (3 - (pos & 0x3)); + /* if process is 32-bit, clear upper 32 bits of EA */ + if ((regs->msr & MSR_64BIT) == 0) + EA &= 0xFFFFFFFF; + switch ((instword & PPC_INST_STRING_MASK)) { case PPC_INST_LSWX: case PPC_INST_LSWI: |