From: Amey Narkhede <ameynarkhede03@gmail.com>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
Amey Narkhede <ameynarkhede03@gmail.com>
Subject: [PATCH] PCI: Check value of resource alignment before using __ffs
Date: Thu, 22 Apr 2021 00:17:47 +0530 [thread overview]
Message-ID: <20210421184747.62391-1-ameynarkhede03@gmail.com> (raw)
Return value of __ffs is undefined if no set bit exists in
its argument. This indicates that the associated BAR has
invalid alignment.
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
---
drivers/pci/setup-bus.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 2ce636937c6e..44e8449418ae 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1044,6 +1044,11 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
* resources.
*/
align = pci_resource_alignment(dev, r);
+ if (!align) {
+ pci_warn(dev, "BAR %d: %pR has bogus alignment\n",
+ i, r);
+ continue;
+ }
order = __ffs(align) - 20;
if (order < 0)
order = 0;
--
2.31.1
next reply other threads:[~2021-04-21 18:48 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-21 18:47 Amey Narkhede [this message]
2021-04-22 6:43 ` [PATCH] PCI: Check value of resource alignment before using __ffs Leon Romanovsky
2021-04-22 9:43 ` Amey Narkhede
2021-04-22 10:41 ` Leon Romanovsky
2021-04-22 10:47 ` Amey Narkhede
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