lkml.org 
[lkml]   [2021]   [Jun]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH stable-5.12.y backport 2/2] KVM: arm64: Resolve all pending PC updates before immediate exit
On Tue, 01 Jun 2021 12:12:38 +0100,
Zenghui Yu <yuzenghui@huawei.com> wrote:
>
> commit e3e880bb1518eb10a4b4bb4344ed614d6856f190 upstream.
>
> Commit 26778aaa134a ("KVM: arm64: Commit pending PC adjustemnts before
> returning to userspace") fixed the PC updating issue by forcing an explicit
> synchronisation of the exception state on vcpu exit to userspace.
>
> However, we forgot to take into account the case where immediate_exit is
> set by userspace and KVM_RUN will exit immediately. Fix it by resolving all
> pending PC updates before returning to userspace.
>
> Since __kvm_adjust_pc() relies on a loaded vcpu context, I moved the
> immediate_exit checking right after vcpu_load(). We will get some overhead
> if immediate_exit is true (which should hopefully be rare).
>
> Fixes: 26778aaa134a ("KVM: arm64: Commit pending PC adjustemnts before returning to userspace")
> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> Link: https://lore.kernel.org/r/20210526141831.1662-1-yuzenghui@huawei.com
> Cc: stable@vger.kernel.org # 5.11

Reviewed-by: Marc Zyngier <maz@kernel.org>

M.

--
Without deviation from the norm, progress is not possible.

\
 
 \ /
  Last update: 2021-06-01 13:45    [W:1.313 / U:0.212 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site