From: Christoph Hellwig <hch@infradead.org>
To: John Garry <john.garry@huawei.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
Christoph Hellwig <hch@infradead.org>,
"Ewan D. Milne" <emilne@redhat.com>,
"James E.J. Bottomley" <jejb@linux.ibm.com>,
"Martin K. Petersen" <martin.petersen@oracle.com>,
Alim Akhtar <alim.akhtar@samsung.com>,
Avri Altman <avri.altman@wdc.com>,
Doug Gilbert <dgilbert@interlog.com>,
linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
james.smart@broadcom.com
Subject: Re: [PATCH 1/4] scsi: core: constify pointer to scsi_host_template
Date: Wed, 11 May 2022 01:31:36 -0700 [thread overview]
Message-ID: <Ynt0aFMX+z/UhGJ2@infradead.org> (raw)
In-Reply-To: <fd2cdc06-5d88-306a-3ee1-7aef3e3b8921@huawei.com>
On Mon, May 09, 2022 at 03:50:33PM +0100, John Garry wrote:
> If you check scsi_device_dev_release(), we try to do a 'get' - if it fails,
> then we nullify hostt->module. I think that is important as then we call
> execute_in_process_context(), whose worker does the 'put'. However, the
> 'put' will get upset if the refcnt was 0, which it would be if the earlier
> 'get' fails - hence the nullify is to avoid that possibility. So whatever
> you do needs to handle that. Details are in f2b85040
Yikes, that code is completely and utterly buggy and does not account
for all the cases why try_module_get can fail. I think we always have
a reference here and could use __module_get, but what we have is
certainly unsafe and a good reason why the host template should be
constifyed.
prev parent reply other threads:[~2022-05-11 8:33 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-08 10:30 [PATCH 1/4] scsi: core: constify pointer to scsi_host_template Krzysztof Kozlowski
2022-04-08 10:30 ` [PATCH 2/4] scsi: core: fix white-spaces Krzysztof Kozlowski
2022-05-04 8:47 ` Krzysztof Kozlowski
2022-04-08 10:30 ` [PATCH 3/4] scsi: ufs: ufshcd-pltfrm: constify pointed data Krzysztof Kozlowski
2022-04-08 10:30 ` [PATCH 4/4] scsi: ufs: ufshcd: " Krzysztof Kozlowski
2022-04-08 14:35 ` Bart Van Assche
2022-04-08 12:14 ` [PATCH 1/4] scsi: core: constify pointer to scsi_host_template John Garry
2022-04-08 12:32 ` Krzysztof Kozlowski
2022-04-08 12:57 ` John Garry
2022-04-08 19:31 ` Ewan D. Milne
2022-04-12 7:57 ` John Garry
2022-04-20 7:03 ` Christoph Hellwig
2022-04-25 8:58 ` John Garry
2022-04-25 9:22 ` Krzysztof Kozlowski
2022-04-25 13:04 ` John Garry
2022-04-26 1:16 ` Bart Van Assche
2022-04-26 1:54 ` Douglas Gilbert
2022-04-26 4:13 ` Bart Van Assche
2022-04-27 1:47 ` Douglas Gilbert
2022-05-06 16:42 ` Krzysztof Kozlowski
2022-05-09 11:28 ` John Garry
2022-05-09 13:20 ` Krzysztof Kozlowski
2022-05-09 14:50 ` John Garry
2022-05-11 8:31 ` Christoph Hellwig [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=Ynt0aFMX+z/UhGJ2@infradead.org \
--to=hch@infradead.org \
--cc=alim.akhtar@samsung.com \
--cc=avri.altman@wdc.com \
--cc=dgilbert@interlog.com \
--cc=emilne@redhat.com \
--cc=james.smart@broadcom.com \
--cc=jejb@linux.ibm.com \
--cc=john.garry@huawei.com \
--cc=krzysztof.kozlowski@linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=martin.petersen@oracle.com \
/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).