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17 May 2024, 11:00:25 UTC
Revision 1a73d9310e093fc3adffba4d0a67b9fab2ee3f63 authored by Paul Burton on 02 June 2017, 18:35:01 UTC, committed by Ralf Baechle on 15 June 2017, 09:47:42 UTC 
MIPS: Fix bnezc/jialc return address calculation
 
The code handling the pop76 opcode (ie. bnezc & jialc instructions) in
__compute_return_epc_for_insn() needs to set the value of $31 in the
jialc case, which is encoded with rs = 0. However its check to
differentiate bnezc (rs != 0) from jialc (rs = 0) was unfortunately
backwards, meaning that if we emulate a bnezc instruction we clobber $31
& if we emulate a jialc instruction it actually behaves like a jic
instruction.

Fix this by inverting the check of rs to match the way the instructions
are actually encoded.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions")
Cc: stable <stable@vger.kernel.org> # v4.0+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16178/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1 parent 698b851
History
Tip revision: 1a73d9310e093fc3adffba4d0a67b9fab2ee3f63 authored by Paul Burton on 02 June 2017, 18:35:01 UTC
MIPS: Fix bnezc/jialc return address calculation
Tip revision: 1a73d93
File Mode Size
binding.txt -rw-r--r-- 3.5 KB
bus.txt -rw-r--r-- 4.0 KB
class.txt -rw-r--r-- 4.4 KB
design-patterns.txt -rw-r--r-- 3.0 KB
device.txt -rw-r--r-- 3.2 KB
devres.txt -rw-r--r-- 9.9 KB
driver.txt -rw-r--r-- 7.4 KB
overview.txt -rw-r--r-- 4.6 KB
platform.txt -rw-r--r-- 10.9 KB
porting.txt -rw-r--r-- 12.8 KB
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