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author | Will Deacon <will@kernel.org> | 2022-03-14 22:05:13 +0300 |
---|---|---|
committer | Will Deacon <will@kernel.org> | 2022-03-14 22:08:31 +0300 |
commit | 641d804157294d9b19bdfe6a2cdbd5d25939a048 (patch) | |
tree | d4e06201998b94999fc1e1ea7cea95b334da9630 /arch/arm64/include/asm/assembler.h | |
parent | 8d93b7a242b2adf36949c10b8eb9cc084a74b59a (diff) | |
parent | 52c9f93a9c482251cb0d224faa602ba26d462be8 (diff) |
Merge branch 'for-next/spectre-bhb' into for-next/core
Merge in the latest Spectre mess to fix up conflicts with what was
already queued for 5.18 when the embargo finally lifted.
* for-next/spectre-bhb: (21 commits)
arm64: Do not include __READ_ONCE() block in assembly files
arm64: proton-pack: Include unprivileged eBPF status in Spectre v2 mitigation reporting
arm64: Use the clearbhb instruction in mitigations
KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated
arm64: Mitigate spectre style branch history side channels
arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2
arm64: Add percpu vectors for EL1
arm64: entry: Add macro for reading symbol addresses from the trampoline
arm64: entry: Add vectors that have the bhb mitigation sequences
arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations
arm64: entry: Allow the trampoline text to occupy multiple pages
arm64: entry: Make the kpti trampoline's kpti sequence optional
arm64: entry: Move trampoline macros out of ifdef'd section
arm64: entry: Don't assume tramp_vectors is the start of the vectors
arm64: entry: Allow tramp_alias to access symbols after the 4K boundary
arm64: entry: Move the trampoline data page before the text page
arm64: entry: Free up another register on kpti's tramp_exit path
arm64: entry: Make the trampoline cleanup optional
KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A
arm64: spectre: Rename spectre_v4_patch_fw_mitigation_conduit
...
Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
-rw-r--r-- | arch/arm64/include/asm/assembler.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 8df412178efb..8c5a61aeaf8e 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -109,6 +109,13 @@ .endm /* + * Clear Branch History instruction + */ + .macro clearbhb + hint #22 + .endm + +/* * Speculation barrier */ .macro sb @@ -845,4 +852,50 @@ alternative_endif #endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */ + .macro __mitigate_spectre_bhb_loop tmp +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY +alternative_cb spectre_bhb_patch_loop_iter + mov \tmp, #32 // Patched to correct the immediate +alternative_cb_end +.Lspectre_bhb_loop\@: + b . + 4 + subs \tmp, \tmp, #1 + b.ne .Lspectre_bhb_loop\@ + sb +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm + + .macro mitigate_spectre_bhb_loop tmp +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY +alternative_cb spectre_bhb_patch_loop_mitigation_enable + b .L_spectre_bhb_loop_done\@ // Patched to NOP +alternative_cb_end + __mitigate_spectre_bhb_loop \tmp +.L_spectre_bhb_loop_done\@: +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm + + /* Save/restores x0-x3 to the stack */ + .macro __mitigate_spectre_bhb_fw +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + stp x0, x1, [sp, #-16]! + stp x2, x3, [sp, #-16]! + mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3 +alternative_cb smccc_patch_fw_mitigation_conduit + nop // Patched to SMC/HVC #0 +alternative_cb_end + ldp x2, x3, [sp], #16 + ldp x0, x1, [sp], #16 +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm + + .macro mitigate_spectre_bhb_clear_insn +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY +alternative_cb spectre_bhb_patch_clearbhb + /* Patched to NOP when not supported */ + clearbhb + isb +alternative_cb_end +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm #endif /* __ASM_ASSEMBLER_H */ |