From: Paolo Bonzini <pbonzini@redhat.com>
To: Borislav Petkov <bp@alien8.de>
Cc: kvm ML <kvm@vger.kernel.org>, lkml <linux-kernel@vger.kernel.org>,
Xiao Guangrong <guangrong.xiao@linux.intel.com>
Subject: Re: include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!
Date: Mon, 21 Sep 2015 17:10:46 +0200 [thread overview]
Message-ID: <56001DF6.3000902@redhat.com> (raw)
In-Reply-To: <20150920164851.GB3540@pd.tnic>
On 20/09/2015 18:48, Borislav Petkov wrote:
> [26421.593927] ------ spte 0x3e5a22027 level 4.
> [26421.598228] ------ spte 0x38a00b027 level 3.
> [26421.602505] ------ spte 0x387334027 level 2.
> [26421.602506] ------ spte 0xffff0000000b8f67 level 1.
> [26421.602506] ------------[ cut here ]------------
> [26421.602530] WARNING: CPU: 2 PID: 17000 at arch/x86/kvm/mmu.c:3385 handle_mmio_page_fault.part.93+0x1a/0x20 [kvm]()
> [26421.602550] Modules linked in: tun sha256_ssse3 sha256_generic drbg binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd fam15h_power amd64_edac_mod k10temp edac_core amdkfd amd_iommu_v2 radeon acpi_cpufreq
> [26421.602552] CPU: 2 PID: 17000 Comm: qemu-system-i38 Not tainted 4.3.0-rc1+ #1
> [26421.602553] Hardware name: To be filled by O.E.M. To be filled by O.E.M./M5A97 EVO R2.0, BIOS 1503 01/16/2013
> [26421.602555] ffffffffa02fc7d2 ffff880386c0fb80 ffffffff812c8c2a 0000000000000000
> [26421.602556] ffff880386c0fbb8 ffffffff81053e55 ffff880429ff8000 000000000000000f
> [26421.602558] 00000000000b8000 0000000000000000 00000000ffffffff ffff880386c0fbc8
> [26421.602558] Call Trace:
> [26421.602564] [<ffffffff812c8c2a>] dump_stack+0x4e/0x84
> [26421.602566] [<ffffffff81053e55>] warn_slowpath_common+0x95/0xe0
> [26421.602567] [<ffffffff81053f5a>] warn_slowpath_null+0x1a/0x20
> [26421.602577] [<ffffffffa02cf73a>] handle_mmio_page_fault.part.93+0x1a/0x20 [kvm]
Can you test this patch for this second call trace?
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index fb16a8ea3dee..10c281ec9a25 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3320,6 +3320,9 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
if (!is_shadow_present_pte(spte))
break;
+ if (leaf == 1 && is_mmio_spte(spte))
+ break;
+
reserved |= is_shadow_zero_bits_set(&vcpu->arch.mmu, spte,
leaf);
}
Thanks,
Paolo
next prev parent reply other threads:[~2015-09-21 15:10 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-20 16:48 include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage! Borislav Petkov
2015-09-21 5:48 ` Paolo Bonzini
2015-09-21 15:10 ` Paolo Bonzini [this message]
2015-09-21 15:19 ` Paolo Bonzini
2015-09-21 15:44 ` Borislav Petkov
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=56001DF6.3000902@redhat.com \
--to=pbonzini@redhat.com \
--cc=bp@alien8.de \
--cc=guangrong.xiao@linux.intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.