From: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>,
kvm@vger.kernel.org, virtualization@lists.linux-foundation.org,
paul.gortmaker@windriver.com, hpa@zytor.com, ak@linux.intel.com,
a.ryabinin@samsung.com, x86@kernel.org, borntraeger@de.ibm.com,
mingo@redhat.com, xen-devel@lists.xenproject.org,
paulmck@linux.vnet.ibm.com, riel@redhat.com,
konrad.wilk@oracle.com, sasha.levin@oracle.com, davej@redhat.com,
tglx@linutronix.de, waiman.long@hp.com, oleg@redhat.com,
linux-kernel@vger.kernel.org, pbonzini@redhat.com,
akpm@linux-foundation.org, torvalds@linux-foundation.org
Subject: Re: [PATCH] x86 spinlock: Fix memory corruption on completing completions
Date: Mon, 09 Feb 2015 18:22:21 +0530 [thread overview]
Message-ID: <54D8AD85.1070409@linux.vnet.ibm.com> (raw)
In-Reply-To: <20150209120227.GT21418@twins.programming.kicks-ass.net>
On 02/09/2015 05:32 PM, Peter Zijlstra wrote:
> On Mon, Feb 09, 2015 at 03:04:22PM +0530, Raghavendra K T wrote:
>> So we have 3 choices,
>> 1. xadd
>> 2. continue with current approach.
>> 3. a read before unlock and also after that.
>
> For the truly paranoid we have probe_kernel_address(), suppose the lock
> was in module space and the module just got unloaded under us.
>
Thanks.. Good idea, How costly is it?
atleast we could do probe_kernel_address() and check the value of
slowpath flag if people as us to address invalid read problem.
next prev parent reply other threads:[~2015-02-09 12:52 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1423234148-13886-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com>
2015-02-06 15:20 ` [PATCH] x86 spinlock: Fix memory corruption on completing completions Sasha Levin
2015-02-06 16:15 ` Linus Torvalds
2015-02-06 17:03 ` Andrey Ryabinin
2015-02-08 17:14 ` Oleg Nesterov
2015-02-06 16:25 ` Linus Torvalds
2015-02-06 19:42 ` Davidlohr Bueso
[not found] ` <1423251764.1057.1.camel@stgolabs.net>
2015-02-06 21:15 ` Sasha Levin
2015-02-06 23:24 ` Davidlohr Bueso
2015-02-08 17:49 ` Raghavendra K T
2015-02-06 18:57 ` Sasha Levin
2015-02-08 17:57 ` Raghavendra K T
2015-02-08 21:14 ` Jeremy Fitzhardinge
[not found] ` <54D7D19B.1000103@goop.org>
2015-02-09 9:34 ` Raghavendra K T
[not found] ` <54D87F1E.9060307@linux.vnet.ibm.com>
2015-02-09 12:02 ` Peter Zijlstra
2015-02-09 12:52 ` Raghavendra K T [this message]
2015-02-10 0:53 ` Linus Torvalds
2015-02-10 9:30 ` Raghavendra K T
2015-02-10 13:18 ` Denys Vlasenko
[not found] ` <CAK1hOcNZ+hfjt=CmtZumPoFQRdQbf9SSEF0cOWv9-9ku0K7bcg@mail.gmail.com>
2015-02-10 13:20 ` Denys Vlasenko
2015-02-10 14:24 ` Oleg Nesterov
2015-02-10 13:23 ` Sasha Levin
2015-02-10 13:26 ` Oleg Nesterov
2015-02-11 1:18 ` Jeremy Fitzhardinge
2015-02-11 17:24 ` Oleg Nesterov
2015-02-11 23:15 ` Jeremy Fitzhardinge
[not found] ` <54DBE27C.8050105@goop.org>
2015-02-11 23:28 ` Linus Torvalds
2015-02-12 7:08 ` Jeremy Fitzhardinge
2015-02-12 14:18 ` Oleg Nesterov
2015-02-11 11:08 ` Raghavendra K T
[not found] ` <54DB384A.2050305@linux.vnet.ibm.com>
2015-02-11 17:38 ` Oleg Nesterov
2015-02-11 18:38 ` Raghavendra K T
2015-02-06 14:49 Raghavendra K T
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=54D8AD85.1070409@linux.vnet.ibm.com \
--to=raghavendra.kt@linux.vnet.ibm.com \
--cc=a.ryabinin@samsung.com \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=borntraeger@de.ibm.com \
--cc=davej@redhat.com \
--cc=hpa@zytor.com \
--cc=jeremy@goop.org \
--cc=konrad.wilk@oracle.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=oleg@redhat.com \
--cc=paul.gortmaker@windriver.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=riel@redhat.com \
--cc=sasha.levin@oracle.com \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=virtualization@lists.linux-foundation.org \
--cc=waiman.long@hp.com \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.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 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).