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authorJean-Philippe Brucker <jean-philippe@linaro.org>2021-07-21 09:18:35 +0200
committerWill Deacon <will@kernel.org>2021-07-21 12:23:25 +0200
commita7c3acca53801e10a77ede6b759a73f5ac4bc261 (patch)
treeaa6739e676233664393b106c706c111b86ff3751
parentarm64: entry: fix KCOV suppression (diff)
downloadlinux-a7c3acca53801e10a77ede6b759a73f5ac4bc261.tar.xz
linux-a7c3acca53801e10a77ede6b759a73f5ac4bc261.zip
arm64: smccc: Save lr before calling __arm_smccc_sve_check()
Commit cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint") added a call to __arm_smccc_sve_check() which clobbers the lr (register x30), causing __arm_smccc_hvc() to return to itself and crash. Save lr on the stack before calling __arm_smccc_sve_check(). Save the frame pointer (x29) to complete the frame record, and adjust the offsets used to access stack parameters. Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Mark Brown <broonie@kernel.org> Fixes: cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint") Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Link: https://lore.kernel.org/r/20210721071834.69130-1-jean-philippe@linaro.org Signed-off-by: Will Deacon <will@kernel.org>
-rw-r--r--arch/arm64/kernel/smccc-call.S9
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/arm64/kernel/smccc-call.S b/arch/arm64/kernel/smccc-call.S
index d3d37f932b97..487381164ff6 100644
--- a/arch/arm64/kernel/smccc-call.S
+++ b/arch/arm64/kernel/smccc-call.S
@@ -32,20 +32,23 @@ SYM_FUNC_END(__arm_smccc_sve_check)
EXPORT_SYMBOL(__arm_smccc_sve_check)
.macro SMCCC instr
+ stp x29, x30, [sp, #-16]!
+ mov x29, sp
alternative_if ARM64_SVE
bl __arm_smccc_sve_check
alternative_else_nop_endif
\instr #0
- ldr x4, [sp]
+ ldr x4, [sp, #16]
stp x0, x1, [x4, #ARM_SMCCC_RES_X0_OFFS]
stp x2, x3, [x4, #ARM_SMCCC_RES_X2_OFFS]
- ldr x4, [sp, #8]
+ ldr x4, [sp, #24]
cbz x4, 1f /* no quirk structure */
ldr x9, [x4, #ARM_SMCCC_QUIRK_ID_OFFS]
cmp x9, #ARM_SMCCC_QUIRK_QCOM_A6
b.ne 1f
str x6, [x4, ARM_SMCCC_QUIRK_STATE_OFFS]
-1: ret
+1: ldp x29, x30, [sp], #16
+ ret
.endm
/*