diff mbox series

[ARM64,v4.4,V3,37/44] arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support

Message ID d41b4ecd51a3337b41c41b67c4adc704f7a766ed.1567077734.git.viresh.kumar@linaro.org (mailing list archive)
State New, archived
Headers show
Series V4.4 backport of arm64 Spectre patches | expand

Commit Message

Viresh Kumar Aug. 29, 2019, 11:34 a.m. UTC 
From: Marc Zyngier <marc.zyngier@arm.com>

commit 6167ec5c9145cdf493722dfd80a5d48bafc4a18a upstream.

A new feature of SMCCC 1.1 is that it offers firmware-based CPU
workarounds. In particular, SMCCC_ARCH_WORKAROUND_1 provides
BP hardening for CVE-2017-5715.

If the host has some mitigation for this issue, report that
we deal with it using SMCCC_ARCH_WORKAROUND_1, as we apply the
host workaround on every guest exit.

Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[ Viresh: Picked on only arm-smccc.h changes ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 include/linux/arm-smccc.h | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index da9f3916f9a9..1f02e4045a9e 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -73,6 +73,11 @@ 
 			   ARM_SMCCC_SMC_32,				\
 			   0, 1)
 
+#define ARM_SMCCC_ARCH_WORKAROUND_1					\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
+			   ARM_SMCCC_SMC_32,				\
+			   0, 0x8000)
+
 #ifndef __ASSEMBLY__
 
 /**