From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
"Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>,
Catalin Marinas <catalin.marinas@arm.com>,
James Morse <james.morse@arm.com>
Subject: [PATCH 4.14 25/27] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated
Date: Fri, 1 Apr 2022 08:36:35 +0200 [thread overview]
Message-ID: <20220401063624.945760820@linuxfoundation.org> (raw)
In-Reply-To: <20220401063624.232282121@linuxfoundation.org>
From: James Morse <james.morse@arm.com>
commit a5905d6af492ee6a4a2205f0d550b3f931b03d03 upstream.
KVM allows the guest to discover whether the ARCH_WORKAROUND SMCCC are
implemented, and to preserve that state during migration through its
firmware register interface.
Add the necessary boiler plate for SMCCC_ARCH_WORKAROUND_3.
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ kvm code moved to virt/kvm/arm, removed fw regs ABI. Added 32bit stub ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm/include/asm/kvm_host.h | 6 ++++++
arch/arm64/include/asm/kvm_host.h | 5 +++++
virt/kvm/arm/psci.c | 12 ++++++++++++
3 files changed, 23 insertions(+)
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -26,6 +26,7 @@
#include <asm/kvm_asm.h>
#include <asm/kvm_mmio.h>
#include <asm/fpstate.h>
+#include <asm/spectre.h>
#include <kvm/arm_arch_timer.h>
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
@@ -324,4 +325,9 @@ static inline int kvm_arm_have_ssbd(void
return KVM_SSBD_UNKNOWN;
}
+static inline int kvm_arm_get_spectre_bhb_state(void)
+{
+ /* 32bit guests don't need firmware for this */
+ return SPECTRE_VULNERABLE; /* aka SMCCC_RET_NOT_SUPPORTED */
+}
#endif /* __ARM_KVM_HOST_H__ */
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -450,4 +450,9 @@ static inline int kvm_arm_have_ssbd(void
}
}
+static inline enum mitigation_state kvm_arm_get_spectre_bhb_state(void)
+{
+ return arm64_get_spectre_bhb_state();
+}
+
#endif /* __ARM64_KVM_HOST_H__ */
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -433,6 +433,18 @@ int kvm_hvc_call_handler(struct kvm_vcpu
break;
}
break;
+ case ARM_SMCCC_ARCH_WORKAROUND_3:
+ switch (kvm_arm_get_spectre_bhb_state()) {
+ case SPECTRE_VULNERABLE:
+ break;
+ case SPECTRE_MITIGATED:
+ val = SMCCC_RET_SUCCESS;
+ break;
+ case SPECTRE_UNAFFECTED:
+ val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
+ break;
+ }
+ break;
}
break;
default:
next prev parent reply other threads:[~2022-04-01 6:39 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-01 6:36 [PATCH 4.14 00/27] 4.14.275-rc1 review Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 01/27] arm64: arch_timer: Add workaround for ARM erratum 1188873 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 02/27] arm64: arch_timer: avoid unused function warning Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 03/27] arm64: Add silicon-errata.txt entry for ARM erratum 1188873 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 04/27] arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 05/27] arm64: Add part number for Neoverse N1 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 06/27] arm64: Add part number for Arm Cortex-A77 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 07/27] arm64: Add Neoverse-N2, Cortex-A710 CPU part definition Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 08/27] arm64: Add Cortex-X2 " Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 09/27] arm64: entry.S: Add ventry overflow sanity checks Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 10/27] arm64: entry: Make the trampoline cleanup optional Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 11/27] arm64: entry: Free up another register on kptis tramp_exit path Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 12/27] arm64: entry: Move the trampoline data page before the text page Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 13/27] arm64: entry: Allow tramp_alias to access symbols after the 4K boundary Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 14/27] arm64: entry: Dont assume tramp_vectors is the start of the vectors Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 15/27] arm64: entry: Move trampoline macros out of ifdefd section Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 16/27] arm64: entry: Make the kpti trampolines kpti sequence optional Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 17/27] arm64: entry: Allow the trampoline text to occupy multiple pages Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 18/27] arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 19/27] arm64: entry: Add vectors that have the bhb mitigation sequences Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 20/27] arm64: entry: Add macro for reading symbol addresses from the trampoline Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 21/27] arm64: Add percpu vectors for EL1 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 22/27] arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2 Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 23/27] KVM: arm64: Add templates for BHB mitigation sequences Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 24/27] arm64: Mitigate spectre style branch history side channels Greg Kroah-Hartman
2022-04-01 6:36 ` Greg Kroah-Hartman [this message]
2022-04-01 6:36 ` [PATCH 4.14 26/27] arm64: add ID_AA64ISAR2_EL1 sys register Greg Kroah-Hartman
2022-04-01 6:36 ` [PATCH 4.14 27/27] arm64: Use the clearbhb instruction in mitigations Greg Kroah-Hartman
2022-04-01 10:43 ` [PATCH 4.14 00/27] 4.14.275-rc1 review Guenter Roeck
2022-04-01 18:26 ` Naresh Kamboju
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220401063624.945760820@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=catalin.marinas@arm.com \
--cc=james.morse@arm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rmk+kernel@armlinux.org.uk \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).