From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: "Krzysztof Wilczyński" <kw@linux.com>,
"Rich Felker" <dalias@libc.org>,
linux-sh@vger.kernel.org, linux-pci@vger.kernel.org,
"Dominik Brodowski" <linux@dominikbrodowski.net>,
linux-mips@vger.kernel.org, "Bjorn Helgaas" <bhelgaas@google.com>,
"Andrew Lunn" <andrew@lunn.ch>,
"Jonas Gorski" <jonas.gorski@gmail.com>,
sparclinux@vger.kernel.org,
"Stefano Stabellini" <sstabellini@kernel.org>,
"Yoshinori Sato" <ysato@users.sourceforge.jp>,
"Gregory Clement" <gregory.clement@bootlin.com>,
"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
"Russell King" <linux@armlinux.org.uk>,
linux-acpi@vger.kernel.org, "Miguel Ojeda" <ojeda@kernel.org>,
xen-devel@lists.xenproject.org,
"Matt Turner" <mattst88@gmail.com>,
"Anatolij Gustschin" <agust@denx.de>,
"Sebastian Hesselbarth" <sebastian.hesselbarth@gmail.com>,
"Arn d Bergmann" <arnd@arndb.de>,
"Niklas Schnelle" <schnelle@linux.ibm.com>
Subject: Re: [PATCH v8 0/7] Add pci_dev_for_each_resource() helper and update users
Date: Mon, 5 Jun 2023 17:04:05 +0300 [thread overview]
Message-ID: <ZH3rVcSr+m8DHmo9@smile.fi.intel.com> (raw)
In-Reply-To: <ZHe8dKb3f392MfBO@bhelgaas>
On Wed, May 31, 2023 at 04:30:28PM -0500, Bjorn Helgaas wrote:
> On Wed, May 31, 2023 at 08:48:35PM +0200, Jonas Gorski wrote:
...
> > Looking at the code I understand where coverity is coming from:
> >
> > #define __pci_dev_for_each_res0(dev, res, ...) \
> > for (unsigned int __b = 0; \
> > res = pci_resource_n(dev, __b), __b < PCI_NUM_RESOURCES; \
> > __b++)
> >
> > res will be assigned before __b is checked for being less than
> > PCI_NUM_RESOURCES, making it point to behind the array at the end of
> > the last loop iteration.
> >
> > Rewriting the test expression as
> >
> > __b < PCI_NUM_RESOURCES && (res = pci_resource_n(dev, __b));
> >
> > should avoid the (coverity) warning by making use of lazy evaluation.
> >
> > It probably makes the code slightly less performant as res will now be
> > checked for being not NULL (which will always be true), but I doubt it
> > will be significant (or in any hot paths).
>
> Thanks a lot for looking into this! I think you're right, and I think
> the rewritten expression is more logical as well. Do you want to post
> a patch for it?
Gimme some time, I was on a long leave and now it's a pile to handle.
--
With Best Regards,
Andy Shevchenko
next prev parent reply other threads:[~2023-06-05 14:04 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-30 16:24 [PATCH v8 0/7] Add pci_dev_for_each_resource() helper and update users Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 1/7] kernel.h: Split out COUNT_ARGS() and CONCATENATE() Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 2/7] PCI: Introduce pci_resource_n() Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 3/7] PCI: Introduce pci_dev_for_each_resource() Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 4/7] PCI: Document pci_bus_for_each_resource() to avoid confusion Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 5/7] PCI: Allow pci_bus_for_each_resource() to take less arguments Andy Shevchenko
2023-04-05 11:50 ` Andy Shevchenko
2023-04-05 20:11 ` Bjorn Helgaas
2023-03-30 16:24 ` [PATCH v8 6/7] EISA: Convert to use less arguments in pci_bus_for_each_resource() Andy Shevchenko
2023-03-30 16:24 ` [PATCH v8 7/7] pcmcia: " Andy Shevchenko
2023-04-05 8:30 ` Andy Shevchenko
2023-04-04 16:11 ` [PATCH v8 0/7] Add pci_dev_for_each_resource() helper and update users Bjorn Helgaas
2023-04-05 8:28 ` Andy Shevchenko
2023-04-05 20:18 ` Bjorn Helgaas
2023-04-06 10:31 ` Andy Shevchenko
2023-05-09 18:21 ` Bjorn Helgaas
2023-05-12 10:56 ` Andy Shevchenko
2023-05-12 19:48 ` Bjorn Helgaas
2023-05-30 21:24 ` Bjorn Helgaas
2023-05-31 18:48 ` Jonas Gorski
2023-05-31 21:30 ` Bjorn Helgaas
2023-06-01 11:17 ` Jonas Gorski
2023-06-05 14:04 ` Andy Shevchenko [this message]
2023-06-01 16:25 ` Andy Shevchenko
2023-06-01 16:27 ` Andy Shevchenko
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=ZH3rVcSr+m8DHmo9@smile.fi.intel.com \
--to=andriy.shevchenko@linux.intel.com \
--cc=agust@denx.de \
--cc=andrew@lunn.ch \
--cc=arnd@arndb.de \
--cc=bhelgaas@google.com \
--cc=dalias@libc.org \
--cc=gregory.clement@bootlin.com \
--cc=helgaas@kernel.org \
--cc=jonas.gorski@gmail.com \
--cc=kw@linux.com \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-mips@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=linux@dominikbrodowski.net \
--cc=mattst88@gmail.com \
--cc=ojeda@kernel.org \
--cc=rafael.j.wysocki@intel.com \
--cc=schnelle@linux.ibm.com \
--cc=sebastian.hesselbarth@gmail.com \
--cc=sparclinux@vger.kernel.org \
--cc=sstabellini@kernel.org \
--cc=xen-devel@lists.xenproject.org \
--cc=ysato@users.sourceforge.jp \
/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 read-only IMAP folder(s) and NNTP newsgroup(s).