[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <7e58200c-814e-3598-155a-9a7e6cc24374@huawei.com>
Date: Mon, 16 Nov 2020 22:57:26 +0800
From: Zenghui Yu <yuzenghui@...wei.com>
To: Marc Zyngier <maz@...nel.org>
CC: <kvmarm@...ts.cs.columbia.edu>,
<linux-arm-kernel@...ts.infradead.org>,
<linux-kernel@...r.kernel.org>, <eric.auger@...hat.com>,
<james.morse@....com>, <julien.thierry.kdev@...il.com>,
<suzuki.poulose@....com>, <wanghaibin.wang@...wei.com>,
Keqian Zhu <zhukeqian1@...wei.com>
Subject: Re: [PATCH 1/2] KVM: arm64: vgic: Forbid invalid userspace
Redistributor accesses
Hi Marc,
On 2020/11/16 22:10, Marc Zyngier wrote:
>> My take is that only if the "[Re]Distributor base address" is specified
>> in the system memory map, will the user-provided kvm_device_attr.offset
>> make sense. And we can then handle the access to the register which is
>> defined by "base address + offset".
>
> I'd tend to agree, but it is just that this is a large change at -rc4.
> I'd rather have a quick fix for 5.10, and a more invasive change for 5.11,
> spanning all the possible vgic devices.
So you prefer fixing it by "return a value that doesn't have the Last
bit set" for v5.10? I'm ok with it and can send v2 for it.
Btw, looking again at the way we handle the user-reading of GICR_TYPER
vgic_mmio_read_v3r_typer(vcpu, addr, len)
it seems that @addr is actually the *offset* of GICR_TYPER (0x0008) and
@addr is unlikely to be equal to last_rdist_typer, which is the *GPA* of
the last RD. Looks like the user-reading of GICR_TYPER.Last is always
broken?
Thanks,
Zenghui
Powered by blists - more mailing lists