On Tue, Dec 19, 2023 at 08:56:41AM +0100, Fabian Godehardt wrote:
> Hi all,
>
> please include b65ba0c362be665192381cc59e3ac3ef6f0dd1e1 also on the
> stable-trees up to v5.10 (i think v5.13 was the first fixed tree).
>
> Serial gadget on AM335X is also affected, breaks with NULL pointer
> references and needs this patch. Here is the patch for the v4.19
> tree, cherry picked and manually applied from original commit
> b65ba0c362be665192381cc59e3ac3ef6f0dd1e1:
>
> >From 483d904168b08cf1497c73516c432bde9ae94055 Mon Sep 17 00:00:00 2001
> From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxx>
> Date: Fri, 28 May 2021 16:04:46 +0200
> Subject: [PATCH] usb: musb: fix MUSB_QUIRK_B_DISCONNECT_99 handling
>
> In commit 92af4fc6ec33 ("usb: musb: Fix suspend with devices
> connected for a64"), the logic to support the
> MUSB_QUIRK_B_DISCONNECT_99 quirk was modified to only conditionally
> schedule the musb->irq_work delayed work.
>
> This commit badly breaks ECM Gadget on AM335X. Indeed, with this
> commit, one can observe massive packet loss:
>
> $ ping 192.168.0.100
> ...
> 15 packets transmitted, 3 received, 80% packet loss, time 14316ms
>
> Reverting this commit brings back a properly functioning ECM
> Gadget. An analysis of the commit seems to indicate that a mistake was
> made: the previous code was not falling through into the
> MUSB_QUIRK_B_INVALID_VBUS_91, but now it is, unless the condition is
> taken.
>
> Changing the logic to be as it was before the problematic commit *and*
> only conditionally scheduling musb->irq_work resolves the regression:
>
> $ ping 192.168.0.100
> ...
> 64 packets transmitted, 64 received, 0% packet loss, time 64475ms
>
> Fixes: 92af4fc6ec33 ("usb: musb: Fix suspend with devices connected for a64")
> Cc: stable@xxxxxxxxxxxxxxx
> Tested-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Tested-by: Drew Fustini <drew@xxxxxxxxxxxxxxx>
> Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20210528140446.278076-1-thomas.petazzoni@xxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
As you did the backport, you too need to sign off on this. Can you
resend this with that properly added?
thanks,
greg k-h
