linux-kernel - Re: [PATCH 3/3] KVM: MMU: mark page dirty only when page is really written

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 02 Aug 2010 15:51:41 +0800
From:	Xiao Guangrong <xiaoguangrong@...fujitsu.com>
To:	Avi Kivity <avi@...hat.com>
CC:	Marcelo Tosatti <mtosatti@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>,
	KVM list <kvm@...r.kernel.org>
Subject: Re: [PATCH 3/3] KVM: MMU: mark page dirty only when page is really
 written



Avi Kivity wrote:
>  On 07/27/2010 06:35 AM, Xiao Guangrong wrote:
>> Mark page dirty only when this page is really written, it's more exacter,
>> and also can fix dirty page marking in speculation path
>>
>> Signed-off-by: Xiao Guangrong<xiaoguangrong@...fujitsu.com>
>> ---
>>   arch/x86/kvm/mmu.c |   47
>> ++++++++++++++++++++++++++++-------------------
>>   1 files changed, 28 insertions(+), 19 deletions(-)
>>
>> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
>> index dd6c192..bcc2173 100644
>> --- a/arch/x86/kvm/mmu.c
>> +++ b/arch/x86/kvm/mmu.c
>> @@ -311,24 +311,42 @@ static bool spte_bits_lost(u64 spte)
>>       if (!is_shadow_present_pte(spte))
>>           return false;
>>
>> -    if (spte&  shadow_accessed_mask)
>> +    if (spte&  shadow_accessed_mask&&
>> +          (!is_writable_pte(spte) || spte&  shadow_dirty_mask))
>>           return false;
>>
> 
> Please add parentheses around bitwise operators to reduce confusion. 
> The rest looks good.
> 

OK, will do it in the new version, thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/