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From: Greg KH <gregkh@linuxfoundation.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-usb@vger.kernel.org,
	syzbot <syzbot+de553c19cb054f174a35@syzkaller.appspotmail.com>,
	Felipe Balbi <felipe.balbi@linux.intel.com>
Subject: Re: [PATCH REPOST] usb: udc: Make tracing aware that usb_ep_alloc_request() can return NULL
Date: Mon, 12 Oct 2026 13:26:18 +0200	[thread overview]
Message-ID: <2026101222-retention-pecan-0061@gregkh> (raw)
In-Reply-To: <20261012094911.wHPc_9lJ@linutronix.de>

On Mon, Oct 12, 2026 at 11:49:11AM +0200, Sebastian Andrzej Siewior wrote:
> The alloc_request callback of the EP can return NULL if it was not able
> to allocate a request. This NULL pointer will then be dereferenced by
> tracing in order to show details about it.

When does that happen?

> Let tracing check the req pointer and if NULL just write 0.

Why not fix up the calling point and if req is NULL, not call the
tracepoint as odds are something went really wrong at that point in
time, right?

thanks,

greg k-h

  parent reply	other threads:[~2026-10-12 11:26 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-10-12  9:49 [PATCH REPOST] usb: udc: Make tracing aware that usb_ep_alloc_request() can return NULL Sebastian Andrzej Siewior
2026-10-12 10:00 ` sashiko-bot
2026-10-12 11:26 ` Greg KH [this message]
2026-10-12 16:29   ` Sebastian Andrzej Siewior

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