From: Sasha Levin <sashal@kernel.org>
To: Greg KH <greg@kroah.com>
Cc: Santosh Sivaraj <santosh@fossix.org>, stable@vger.kernel.org
Subject: Re: Random memory corruption may occur due to incorrent tlb flushes
Date: Tue, 18 Feb 2020 10:21:36 -0500 [thread overview]
Message-ID: <20200218152136.GL1734@sasha-vm> (raw)
In-Reply-To: <20200218084901.GA2285287@kroah.com>
On Tue, Feb 18, 2020 at 09:49:01AM +0100, Greg KH wrote:
>On Tue, Feb 18, 2020 at 01:41:07PM +0530, Santosh Sivaraj wrote:
>> Hi Greg/Sasha,
>>
>> The commit a46cc7a90fd (powerpc/mm/radix: Improve
>> TLB/PWC flushes) picked up in 4.14 release has the potential to cause random
>> memory corruption. This was fixed in 5.5 by the following patches.
>>
>> 12e4d53f3f powerpc/mmu_gather: enable RCU_TABLE_FREE even for !SMP case
>> 0ed1325967 mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush
>> 0758cd8304 asm-generic/tlb: avoid potential double flush
>>
>> It's a bit tricky to backport to 4.14 stable (though I have a backport to 4.19
>> stable, which I will post shortly). If you think it's important to fix this in
>> 4.14, it would easier to revert the above mentioned commit (a46cc7a90fd).
>>
>> Please let me know your thoughts.
>
>A revert is probably best, can you send it?
This is a bit tricky because a46cc7a90fd wasn't picked up by as, but
rather is part of the 4.14 kernel. Please make sure you Cc the revert to
the PowerPC mm folks so they could give it a careful review, as it's
much more complex than just reverting a stable commit we queued up.
--
Thanks,
Sasha
prev parent reply other threads:[~2020-02-18 15:21 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-18 8:11 Random memory corruption may occur due to incorrent tlb flushes Santosh Sivaraj
2020-02-18 8:49 ` Greg KH
2020-02-18 15:21 ` Sasha Levin [this message]
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=20200218152136.GL1734@sasha-vm \
--to=sashal@kernel.org \
--cc=greg@kroah.com \
--cc=santosh@fossix.org \
--cc=stable@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 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).