From: Marc Zyngier <maz@kernel.org>
To: Zenghui Yu <yuzenghui@huawei.com>
Cc: Julien Grall <julien@xen.org>,
kvm@vger.kernel.org, Suzuki K Poulose <suzuki.poulose@arm.com>,
Andre Przywara <Andre.Przywara@arm.com>,
Eric Auger <eric.auger@redhat.com>,
James Morse <james.morse@arm.com>,
Julien Thierry <julien.thierry.kdev@gmail.com>,
kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 1/3] KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read
Date: Wed, 15 Apr 2020 14:27:21 +0100 [thread overview]
Message-ID: <de0b9e06fe77238f18ffd8f1bf2f870e@kernel.org> (raw)
In-Reply-To: <190b57e6-0ac5-63bb-57d8-5bab2aea0b2c@huawei.com>
Hi Zenghui,
On 2020-04-15 14:15, Zenghui Yu wrote:
> Hi Marc,
>
> On 2020/4/14 18:35, Marc Zyngier wrote:
>> When a guest tries to read the active state of its interrupts,
>> we currently just return whatever state we have in memory. This
>> means that if such an interrupt lives in a List Register on another
>> CPU, we fail to obsertve the latest active state for this interrupt.
>>
>> In order to remedy this, stop all the other vcpus so that they exit
>> and we can observe the most recent value for the state.
>>
>> Reported-by: Julien Grall <julien@xen.org>
>> Signed-off-by: Marc Zyngier <maz@kernel.org>
>> ---
>> virt/kvm/arm/vgic/vgic-mmio-v2.c | 4 +-
>> virt/kvm/arm/vgic/vgic-mmio-v3.c | 4 +-
>> virt/kvm/arm/vgic/vgic-mmio.c | 100
>> ++++++++++++++++++++-----------
>> virt/kvm/arm/vgic/vgic-mmio.h | 3 +
>> 4 files changed, 71 insertions(+), 40 deletions(-)
>>
>> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c
>> b/virt/kvm/arm/vgic/vgic-mmio-v2.c
>> index 5945f062d749..d63881f60e1a 100644
>> --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c
>> +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c
>> @@ -422,11 +422,11 @@ static const struct vgic_register_region
>> vgic_v2_dist_registers[] = {
>> VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET,
>> vgic_mmio_read_active, vgic_mmio_write_sactive,
>> - NULL, vgic_mmio_uaccess_write_sactive, 1,
>> + vgic_uaccess_read_active, vgic_mmio_uaccess_write_sactive, 1,
>> VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR,
>> vgic_mmio_read_active, vgic_mmio_write_cactive,
>> - NULL, vgic_mmio_uaccess_write_cactive, 1,
>> + vgic_uaccess_read_active, vgic_mmio_uaccess_write_cactive, 1,
>> VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PRI,
>> vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,
>> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> index e72dcc454247..77c8ba1a2535 100644
>> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> @@ -553,11 +553,11 @@ static const struct vgic_register_region
>> vgic_v3_dist_registers[] = {
>> VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISACTIVER,
>> vgic_mmio_read_active, vgic_mmio_write_sactive,
>> - NULL, vgic_mmio_uaccess_write_sactive, 1,
>> + vgic_uaccess_read_active, vgic_mmio_uaccess_write_sactive, 1,
>> VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICACTIVER,
>> vgic_mmio_read_active, vgic_mmio_write_cactive,
>> - NULL, vgic_mmio_uaccess_write_cactive,
>> + vgic_uaccess_read_active, vgic_mmio_uaccess_write_cactive,
>> 1, VGIC_ACCESS_32bit),
>> REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IPRIORITYR,
>> vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,
>
> Shouldn't we also set this uaccess_read cb for GICR_I{S,C}ACTIVER0?
Duh. Yes, of course...
M.
--
Jazz is not dead. It just smells funny...
_______________________________________________
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:[~2020-04-15 13:27 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-14 10:35 [PATCH 0/3] KVM: arm: vgic fixes for 5.7 Marc Zyngier
2020-04-14 10:35 ` [PATCH 1/3] KVM: arm: vgic: Synchronize the whole guest on GIC{D, R}_I{S, C}ACTIVER read Marc Zyngier
2020-04-14 11:16 ` [PATCH 1/3] KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read André Przywara
2020-04-14 13:43 ` Marc Zyngier
2020-04-15 13:15 ` Zenghui Yu
2020-04-15 13:27 ` Marc Zyngier [this message]
2020-04-14 10:35 ` [PATCH 2/3] KVM: arm: vgic: Only use the virtual state when userspace accesses enable bits Marc Zyngier
2020-04-14 10:35 ` [PATCH 3/3] KVM: arm: vgic-v2: Only use the virtual state when userspace accesses pending bits 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=de0b9e06fe77238f18ffd8f1bf2f870e@kernel.org \
--to=maz@kernel.org \
--cc=Andre.Przywara@arm.com \
--cc=eric.auger@redhat.com \
--cc=james.morse@arm.com \
--cc=julien.thierry.kdev@gmail.com \
--cc=julien@xen.org \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=suzuki.poulose@arm.com \
--cc=yuzenghui@huawei.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).