-----Original Message----- From: Jakub Kicinski kuba@kernel.org Sent: Monday, February 6, 2023 9:33 PM To: Haiyang Zhang haiyangz@microsoft.com Cc: linux-hyperv@vger.kernel.org; netdev@vger.kernel.org; Dexuan Cui decui@microsoft.com; KY Srinivasan kys@microsoft.com; Paul Rosswurm paulros@microsoft.com; olaf@aepfle.de; vkuznets@redhat.com; davem@davemloft.net; wei.liu@kernel.org; edumazet@google.com; pabeni@redhat.com; leon@kernel.org; Long Li longli@microsoft.com; ssengar@linux.microsoft.com; linux-kernel@vger.kernel.org; stable@vger.kernel.org Subject: Re: [PATCH net,v3] net: mana: Fix accessing freed irq affinity_hint
On Mon, 6 Feb 2023 13:28:49 -0800 Haiyang Zhang wrote:
After calling irq_set_affinity_and_hint(), the cpumask pointer is saved in desc->affinity_hint, and will be used later when reading /proc/irq/<num>/affinity_hint. So the cpumask variable needs to be persistent. Otherwise, we are accessing freed memory when reading the affinity_hint file.
Also, need to clear affinity_hint before free_irq(), otherwise there is a one-time warning and stack trace during module unloading:
What's the difference from the previous posting? Did you just resend it?
Previously, it failed the auto-check due to some people were not CC-ed. I resent it with more CCs.
Thanks, - Haiyang