arm64: Implement branch predictor hardening for Falkor

Falkor is susceptible to branch predictor aliasing and can
theoretically be attacked by malicious code. This patch
implements a mitigation for these attacks, preventing any
malicious entries from affecting other victim contexts.

Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
[will: fix label name when !CONFIG_KVM and remove references to MIDR_FALKOR]
Signed-off-by: Will Deacon <will.deacon@arm.com>

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Shanker Donthineni
2018-01-05 14:28:59 -06:00
committed by Catalin Marinas
parent aa6acde65e
commit ec82b567a7
6 changed files with 70 additions and 3 deletions

View File

@@ -196,3 +196,15 @@ alternative_endif
eret
ENDPROC(__fpsimd_guest_restore)
ENTRY(__qcom_hyp_sanitize_btac_predictors)
/**
* Call SMC64 with Silicon provider serviceID 23<<8 (0xc2001700)
* 0xC2000000-0xC200FFFF: assigned to SiP Service Calls
* b15-b0: contains SiP functionID
*/
movz x0, #0x1700
movk x0, #0xc200, lsl #16
smc #0
ret
ENDPROC(__qcom_hyp_sanitize_btac_predictors)