github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-22 04:34:03 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

kselftest/arm64: Don't write to P0 in irritator on SME only systems

Browse Source 
Commit 3e360ef0c0 ("kselftest/arm64: Corrupt P0 in the irritator when
testing SSVE") added corruption of P0 to the sve-test case in order to
ensure that the predicate registers were covered as part of the
corruption.  On SME only systems this results in an illegal instruction
since signal handlers are run out of streaming mode and the predicate
registers do not exist out of streaming mode without SVE.  Switch to
entering and exiting streaming mode in the irritator, this will reset
all relevant registers to 0 if they somehow weren't already by the
signal entry.

Fixes: 3e360ef0c0 ("kselftest/arm64: Corrupt P0 in the irritator when testing SSVE")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Mark Brown 2026-07-31 21:50:52 +01:00 committed by Will Deacon
parent 21e37da120
commit 2b989c411a
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
tools/testing/selftests/arm64/fp/sve-test.S
View File

@ -298,15 +298,20 @@ function irritator_handler
add x0, x0, #1
str x0, [x2, #ucontext_regs + 8 * 23]
#ifndef SSVE
// Corrupt some random Z-regs
movi v0.8b, #1
movi v9.16b, #2
movi v31.8b, #3
// And P0
ptrue p0.d
#ifndef SSVE
// And FFR
wrffr p15.b
#else
// Enter and exit streaming mode, will reset all of the V, Z, P
// and FFR registers that the system has.
smstart_sm
smstop
#endif
ret