From: Bjorn Helgaas <helgaas@kernel•org>
To: Jonas Gorski <jonas.gorski@gmail•com>
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>,
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>,
"Arnd Bergmann" <arnd@arndb•de>,
"Niklas Schnelle" <schnelle@linux•ibm.com>,
"Richard Henderson" <richard.henderson@linaro•org>,
"Nicholas Piggin" <npiggin@gmail•com>,
"Ivan Kokshaysky" <ink@jurassic•park.msu.ru>,
"John Paul Adrian Glaubitz" <glaubitz@physik•fu-berlin.de>,
"Mickaël Salaün" <mic@digikod•net>,
"Andy Shevchenko" <andriy.shevchenko@linux•intel.com>,
"Mika Westerberg" <mika.westerberg@linux•intel.com>,
linux-arm-kernel@lists•infradead.org,
"Juergen Gross" <jgross@suse•com>,
"Thomas Bogendoerfer" <tsbogend@alpha•franken.de>,
"Philippe Mathieu-Daudé" <philmd@linaro•org>,
"Pali Rohár" <pali@kernel•org>,
"Randy Dunlap" <rdunlap@infradead•org>,
linux-kernel@vger•kernel.org,
"Oleksandr Tyshchenko" <oleksandr_tyshchenko@epam•com>,
linux-alpha@vger•kernel.org, linuxppc-dev@lists•ozlabs.org,
"David S. Miller" <davem@davemloft•net>,
"Maciej W. Rozycki" <macro@orcam•me.uk>
Subject: Re: [PATCH v8 0/7] Add pci_dev_for_each_resource() helper and update users
Date: Wed, 31 May 2023 16:30:28 -0500 [thread overview]
Message-ID: <ZHe8dKb3f392MfBO@bhelgaas> (raw)
In-Reply-To: <CAOiHx==5YWhDiZP2PyHZiJrmtqRzvqCqoSO59RwuYuR85BezBg@mail.gmail.com>
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?
Bjorn
next prev parent reply other threads:[~2023-05-31 21:31 UTC|newest]
Thread overview: 24+ 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
[not found] ` <CAOiHx==5YWhDiZP2PyHZiJrmtqRzvqCqoSO59RwuYuR85BezBg@mail.gmail.com>
2023-05-31 21:30 ` Bjorn Helgaas [this message]
2023-06-01 11:17 ` Jonas Gorski
2023-06-05 14:04 ` Andy Shevchenko
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=ZHe8dKb3f392MfBO@bhelgaas \
--to=helgaas@kernel$(echo .)org \
--cc=agust@denx$(echo .)de \
--cc=andrew@lunn$(echo .)ch \
--cc=andriy.shevchenko@linux$(echo .)intel.com \
--cc=arnd@arndb$(echo .)de \
--cc=bhelgaas@google$(echo .)com \
--cc=dalias@libc$(echo .)org \
--cc=davem@davemloft$(echo .)net \
--cc=glaubitz@physik$(echo .)fu-berlin.de \
--cc=gregory.clement@bootlin$(echo .)com \
--cc=ink@jurassic$(echo .)park.msu.ru \
--cc=jgross@suse$(echo .)com \
--cc=jonas.gorski@gmail$(echo .)com \
--cc=kw@linux$(echo .)com \
--cc=linux-acpi@vger$(echo .)kernel.org \
--cc=linux-alpha@vger$(echo .)kernel.org \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linux-mips@vger$(echo .)kernel.org \
--cc=linux-pci@vger$(echo .)kernel.org \
--cc=linux-sh@vger$(echo .)kernel.org \
--cc=linux@armlinux$(echo .)org.uk \
--cc=linux@dominikbrodowski$(echo .)net \
--cc=linuxppc-dev@lists$(echo .)ozlabs.org \
--cc=macro@orcam$(echo .)me.uk \
--cc=mattst88@gmail$(echo .)com \
--cc=mic@digikod$(echo .)net \
--cc=mika.westerberg@linux$(echo .)intel.com \
--cc=npiggin@gmail$(echo .)com \
--cc=ojeda@kernel$(echo .)org \
--cc=oleksandr_tyshchenko@epam$(echo .)com \
--cc=pali@kernel$(echo .)org \
--cc=philmd@linaro$(echo .)org \
--cc=rafael.j.wysocki@intel$(echo .)com \
--cc=rdunlap@infradead$(echo .)org \
--cc=richard.henderson@linaro$(echo .)org \
--cc=schnelle@linux$(echo .)ibm.com \
--cc=sebastian.hesselbarth@gmail$(echo .)com \
--cc=sparclinux@vger$(echo .)kernel.org \
--cc=sstabellini@kernel$(echo .)org \
--cc=tsbogend@alpha$(echo .)franken.de \
--cc=xen-devel@lists$(echo .)xenproject.org \
--cc=ysato@users$(echo .)sourceforge.jp \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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