On Mon, Aug 19, 2024, Krishna Kurapati wrote:
On 8/8/2024 5:35 PM, Selvarasu Ganesan wrote:
This commit addresses an issue where the USB core could access an invalid event buffer address during runtime suspend, potentially causing SMMU faults and other memory issues. The problem arises from the following sequence. 1. In dwc3_gadget_suspend, there is a chance of a timeout when moving the USB core to the halt state after clearing the run/stop bit by software. 2. In dwc3_core_exit, the event buffer is cleared regardless of the USB core's status, which may lead to an SMMU faults and other memory issues. if the USB core tries to access the event buffer address.
To prevent this issue, this commit ensures that the event buffer address is not cleared by software when the USB core is active during runtime suspend by checking its status before clearing the buffer address.
Cc: stable@vger.kernel.org Fixes: 89d7f9629946 ("usb: dwc3: core: Skip setting event buffers for host only controllers")
I don't think the fixes tag is right.
This fix is independent of whether controller is host only capable or not. This is fixing the original commit that introduced the cleanup call.
You're reviewing outdated patch. This was brought up to attention prior[*]. The latest patch is v3, which does not have this Fixes tag.
[*] https://lore.kernel.org/linux-usb/8526e46f-30f2-4f24-8874-624b66aa54b1@samsu...
Thanks, Thinh