When using svcr_in to check ZA and Streaming Mode, we should make sure that the value in x2 is correct, otherwise it may trigger an Illegal instruction if FEAT_SVE and !FEAT_SME.
Fixes: 43e3f85523e4 ("kselftest/arm64: Add SME support to syscall ABI test") Signed-off-by: Weizhao Ouyang o451686892@gmail.com --- .../selftests/arm64/abi/syscall-abi-asm.S | 32 +++++++++---------- 1 file changed, 15 insertions(+), 17 deletions(-)
diff --git a/tools/testing/selftests/arm64/abi/syscall-abi-asm.S b/tools/testing/selftests/arm64/abi/syscall-abi-asm.S index df3230fdac39..66ab2e0bae5f 100644 --- a/tools/testing/selftests/arm64/abi/syscall-abi-asm.S +++ b/tools/testing/selftests/arm64/abi/syscall-abi-asm.S @@ -81,32 +81,31 @@ do_syscall: stp x27, x28, [sp, #96]
// Set SVCR if we're doing SME - cbz x1, 1f + cbz x1, load_gpr adrp x2, svcr_in ldr x2, [x2, :lo12:svcr_in] msr S3_3_C4_C2_2, x2 -1:
// Load ZA and ZT0 if enabled - uses x12 as scratch due to SME LDR - tbz x2, #SVCR_ZA_SHIFT, 1f + tbz x2, #SVCR_ZA_SHIFT, load_gpr mov w12, #0 ldr x2, =za_in -2: _ldr_za 12, 2 +1: _ldr_za 12, 2 add x2, x2, x1 add x12, x12, #1 cmp x1, x12 - bne 2b + bne 1b
// ZT0 mrs x2, S3_0_C0_C4_5 // ID_AA64SMFR0_EL1 ubfx x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \ #ID_AA64SMFR0_EL1_SMEver_WIDTH - cbz x2, 1f + cbz x2, load_gpr adrp x2, zt_in add x2, x2, :lo12:zt_in _ldr_zt 2 -1:
+load_gpr: // Load GPRs x8-x28, and save our SP/FP for later comparison ldr x2, =gpr_in add x2, x2, #64 @@ -125,9 +124,9 @@ do_syscall: str x30, [x2], #8 // LR
// Load FPRs if we're not doing neither SVE nor streaming SVE - cbnz x0, 1f + cbnz x0, check_sve_in ldr x2, =svcr_in - tbnz x2, #SVCR_SM_SHIFT, 1f + tbnz x2, #SVCR_SM_SHIFT, check_sve_in
ldr x2, =fpr_in ldp q0, q1, [x2] @@ -148,8 +147,8 @@ do_syscall: ldp q30, q31, [x2, #16 * 30]
b 2f -1:
+check_sve_in: // Load the SVE registers if we're doing SVE/SME
ldr x2, =z_in @@ -256,32 +255,31 @@ do_syscall: stp q30, q31, [x2, #16 * 30]
// Save SVCR if we're doing SME - cbz x1, 1f + cbz x1, check_sve_out mrs x2, S3_3_C4_C2_2 adrp x3, svcr_out str x2, [x3, :lo12:svcr_out] -1:
// Save ZA if it's enabled - uses x12 as scratch due to SME STR - tbz x2, #SVCR_ZA_SHIFT, 1f + tbz x2, #SVCR_ZA_SHIFT, check_sve_out mov w12, #0 ldr x2, =za_out -2: _str_za 12, 2 +1: _str_za 12, 2 add x2, x2, x1 add x12, x12, #1 cmp x1, x12 - bne 2b + bne 1b
// ZT0 mrs x2, S3_0_C0_C4_5 // ID_AA64SMFR0_EL1 ubfx x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \ #ID_AA64SMFR0_EL1_SMEver_WIDTH - cbz x2, 1f + cbz x2, check_sve_out adrp x2, zt_out add x2, x2, :lo12:zt_out _str_zt 2 -1:
+check_sve_out: // Save the SVE state if we have some cbz x0, 1f
On Wed, Dec 11, 2024 at 07:16:39PM +0800, Weizhao Ouyang wrote:
When using svcr_in to check ZA and Streaming Mode, we should make sure that the value in x2 is correct, otherwise it may trigger an Illegal instruction if FEAT_SVE and !FEAT_SME.
Reviewed-by: Mark Brown broonie@kernel.org
Thanks for spotting this.
On Wed, 11 Dec 2024 19:16:39 +0800, Weizhao Ouyang wrote:
When using svcr_in to check ZA and Streaming Mode, we should make sure that the value in x2 is correct, otherwise it may trigger an Illegal instruction if FEAT_SVE and !FEAT_SME.
Applied to arm64 (for-next/fixes), thanks!
[1/1] kselftest/arm64: abi: fix SVCR detection https://git.kernel.org/arm64/c/ce03573a1917
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