mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Markus Elfring <Markus.Elfring@web.de>
To: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>,
	linux-pci@vger.kernel.org, "Bjorn Helgaas" <bhelgaas@google.com>
Cc: stable@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
	kernel-janitors@vger.kernel.org,
	"Christian König" <christian.koenig@amd.com>,
	"D Scott Phillips" <scott@os.amperecomputing.com>,
	"Krzysztof Wilczyński" <kw@linux.com>, "Rio Liu" <rio@r26.me>,
	"Tudor Ambarus" <tudor.ambarus@linaro.org>
Subject: Re: [PATCH v2 1/3] PCI: Relaxed tail alignment should never increase min_align
Date: Thu, 21 Aug 2025 19:00:10 +0200	[thread overview]
Message-ID: <0185a58e-9211-4c10-bcf2-bbf2f566323e@web.de> (raw)
In-Reply-To: <21e11870-f125-e9e7-04f3-ade94d6be6b1@linux.intel.com>

>> …
>> +++ b/drivers/pci/setup-bus.c
>> …
>> @@ -1261,8 +1263,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
>>  		if (bus->self && size1 &&
>>  		    !pbus_upstream_space_available(bus, mask | IORESOURCE_PREFETCH, type,
>>  						   size1, add_align)) {
>> -			min_align = 1ULL << (max_order + __ffs(SZ_1M));
>> -			min_align = max(min_align, win_align);
>> +			relaxed_align = 1ULL << (max_order + __ffs(SZ_1M));
>> +			relaxed_align = max(min_align, win_align);
>> …
>>
>> I wonder why a variable content would be overwritten here
>> without using the previous value.
>> https://cwe.mitre.org/data/definitions/563.html
…> This looks a very good catch. I think it too should have been:
> 
> relaxed_align = max(relaxed_align, win_align);
> 
> ...like in the other case.

Did any known source code analysis tools point such a questionable implementation detail out
for further development considerations?

Regards,
Markus

  reply	other threads:[~2025-08-21 17:00 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-30 14:26 [PATCH v2 0/3] PCI: Resource fitting algorith fixes Ilpo Järvinen
2025-06-30 14:26 ` [PATCH v2 1/3] PCI: Relaxed tail alignment should never increase min_align Ilpo Järvinen
2025-08-21 15:10   ` Bjorn Helgaas
2025-08-21 15:15     ` Ilpo Järvinen
2025-08-21 15:24       ` Ilpo Järvinen
2025-08-21 15:47         ` Bjorn Helgaas
2025-08-21 16:28   ` Markus Elfring
2025-08-21 16:45     ` Ilpo Järvinen
2025-08-21 17:00       ` Markus Elfring [this message]
2025-06-30 14:26 ` [PATCH v2 2/3] PCI: Fix pdev_resources_assignable() disparity Ilpo Järvinen
2025-08-21 15:11   ` Bjorn Helgaas
2025-08-21 15:21     ` Ilpo Järvinen
2025-06-30 14:26 ` [PATCH v2 3/3] PCI: Fix failure detection during resource resize Ilpo Järvinen
2025-08-21 15:14   ` Bjorn Helgaas
2025-08-21 15:22     ` Ilpo Järvinen
2025-07-23 13:07 ` [PATCH v2 0/3] PCI: Resource fitting algorith fixes Ilpo Järvinen
2025-08-21 14:58   ` Ilpo Järvinen
2025-08-21 15:17 ` Bjorn Helgaas

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=0185a58e-9211-4c10-bcf2-bbf2f566323e@web.de \
    --to=markus.elfring@web.de \
    --cc=bhelgaas@google.com \
    --cc=christian.koenig@amd.com \
    --cc=ilpo.jarvinen@linux.intel.com \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=kw@linux.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=rio@r26.me \
    --cc=scott@os.amperecomputing.com \
    --cc=stable@vger.kernel.org \
    --cc=tudor.ambarus@linaro.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

all inboxes | Powered by JetHome®