diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2024-07-23 16:14:54 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2024-07-29 16:58:14 +0100 |
| commit | b42ba4ea4322357fcbfcb0e6e613d79ede84de64 (patch) | |
| tree | 98e14b763d94726fa9827e1db7d71d68d977991c /target | |
| parent | b69c95e718ba83fac6d5d725c4a79c4da808ab67 (diff) | |
target/xtensa: Make use of 'segment' in pptlb helper less confusing
Coverity gets confused about the use of the 'segment' variable in the
pptlb helper function: it thinks that we can take a code path where
we first initialize it:
unsigned segment = XTENSA_MPU_PROBE_B; // 0x40000000
and then use that value as a shift count:
} else if (nhits == 1 && (env->sregs[MPUENB] & (1u << segment))) {
In fact this isn't possible, beacuse xtensa_mpu_lookup() is passed
'&segment', and it uses that as an output value, which it will always
set if it returns nonzero. But the way the code is currently written
is confusing to a human reader as well as to Coverity.
Instead of initializing 'segment' at the top of the function with a
value that's only used in the "nhits == 0" code path, use the
constant value directly in that code path, and don't initialize
segment. This matches the way we use xtensa_mpu_lookup() in its
other callsites in get_physical_addr_mpu().
Resolves: Coverity CID 1547589
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Message-id: 20240723151454.1396826-1-peter.maydell@linaro.org
Diffstat (limited to 'target')
| -rw-r--r-- | target/xtensa/mmu_helper.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/target/xtensa/mmu_helper.c b/target/xtensa/mmu_helper.c index 997b21d389..29b84d5dbf 100644 --- a/target/xtensa/mmu_helper.c +++ b/target/xtensa/mmu_helper.c @@ -991,7 +991,7 @@ uint32_t HELPER(rptlb1)(CPUXtensaState *env, uint32_t s) uint32_t HELPER(pptlb)(CPUXtensaState *env, uint32_t v) { unsigned nhits; - unsigned segment = XTENSA_MPU_PROBE_B; + unsigned segment; unsigned bg_segment; nhits = xtensa_mpu_lookup(env->mpu_fg, env->config->n_mpu_fg_segments, @@ -1005,7 +1005,7 @@ uint32_t HELPER(pptlb)(CPUXtensaState *env, uint32_t v) xtensa_mpu_lookup(env->config->mpu_bg, env->config->n_mpu_bg_segments, v, &bg_segment); - return env->config->mpu_bg[bg_segment].attr | segment; + return env->config->mpu_bg[bg_segment].attr | XTENSA_MPU_PROBE_B; } } |