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Miller" , Andrew Lunn , Eric Dumazet , Nicolai Buchwitz , Paolo Abeni , Ronald Wahl , Yicong Hui , linux-kernel@vger.kernel.org, Thomas Gleixner Subject: Re: [net,PATCH v2] net: ks8851: Reinstate disabling of BHs around IRQ handler Message-ID: <20260413161000.P_SLxmZl@linutronix.de> References: <20260408162535.98108-1-marex@nabladev.com> <20260412090141.21bf1534@kernel.org> <2558832d-c821-436d-898d-b708c5e0a228@nabladev.com> <20260412105125.48f0c58f@kernel.org> <20260413125744.TVKkZcEK@linutronix.de> <20260413084445.59fe28d6@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20260413084445.59fe28d6@kernel.org> On 2026-04-13 08:44:45 [-0700], Jakub Kicinski wrote: > On Mon, 13 Apr 2026 14:57:44 +0200 Sebastian Andrzej Siewior wrote: > > On 2026-04-12 10:51:25 [-0700], Jakub Kicinski wrote: > > > > Does the backtrace make the problem clearer, with the annotation ab= ove ? =20 > > >=20 > > > Sebastian, do you have any recommendation here? tl;dr is that the dri= ver does =20 > > =E2=80=A6 > >=20 > > What about this: >=20 > Thanks for taking a look (according to you auto-reply immediately after > a vacation ;)) ;) > TBH changing the driver feels like a workaround / invitation for a > whack-a-mole game. I'd prefer to fix the skb allocation. The problem is that _irq() implicitly disables bh processing but this does not happen. Forcing this is possible but expensive. However, I did remove lock from bh_disable() on RT. Marek: from which kernel version was this backtrace? > Is there any way we can check if any locks which were _irq() on non-RT > are held? lockdep has a list of locks which are acquired but it does not see if it is _irq() or not. It only records it was acquired. Sebastian