From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
linux-arm-kernel@lists.infradead.org
Cc: kernel-team@android.com, James Morse <james.morse@arm.com>,
stable@vger.kernel.org,
Julien Thierry <julien.thierry.kdev@gmail.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>
Subject: [PATCH 1/2] KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts
Date: Tue, 9 Jun 2020 09:49:20 +0100 [thread overview]
Message-ID: <20200609084921.1448445-2-maz@kernel.org> (raw)
In-Reply-To: <20200609084921.1448445-1-maz@kernel.org>
AArch32 CP1x registers are overlayed on their AArch64 counterparts
in the vcpu struct. This leads to an interesting problem as they
are stored in their CPU-local format, and thus a CP1x register
doesn't "hit" the lower 32bit portion of the AArch64 register on
a BE host.
To workaround this unfortunate situation, introduce a bias trick
in the vcpu_cp1x() accessors which picks the correct half of the
64bit register.
Cc: stable@vger.kernel.org
Reported-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/include/asm/kvm_host.h | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 59029e90b557..e80c0e06f235 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -404,8 +404,14 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg);
* CP14 and CP15 live in the same array, as they are backed by the
* same system registers.
*/
-#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)])
-#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)])
+#ifdef CPU_BIG_ENDIAN
+#define CPx_OFFSET 1
+#else
+#define CPx_OFFSET 0
+#endif
+
+#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_OFFSET])
+#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_OFFSET])
struct kvm_vm_stat {
ulong remote_tlb_flush;
--
2.26.2
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-06-09 8:50 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-09 8:49 [PATCH 0/2] KVM: arm64: Additional 32bit fixes Marc Zyngier
2020-06-09 8:49 ` Marc Zyngier [this message]
2020-06-09 11:41 ` [PATCH 1/2] KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts Robin Murphy
2020-06-09 11:48 ` Marc Zyngier
2020-06-10 14:12 ` James Morse
2020-06-09 8:49 ` [PATCH 2/2] KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception Marc Zyngier
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=20200609084921.1448445-2-maz@kernel.org \
--to=maz@kernel.org \
--cc=james.morse@arm.com \
--cc=julien.thierry.kdev@gmail.com \
--cc=kernel-team@android.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=stable@vger.kernel.org \
--cc=suzuki.poulose@arm.com \
/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).