From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 040AC47A0CD; Tue, 16 Jun 2026 17:39:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781631592; cv=none; b=HN+fsMH+c2J7NHpzKeilFjQmR+UhtrCkL9eCClxlMj3OqYp4rQYnK6F6F1ZoYOQpam+3t7UUUimLbpU7ac3r9Mx8tQTbuWJO3W2iM7xwciZX434I7NETbSH0T1k/eM/qy4kRpgtPPU0lp1aEBVhuQUDaKPRIvTT0BzqOtQQyoYM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781631592; c=relaxed/simple; bh=jFbiGCLB0ua/nTPltSAAHbq+x862qNnbZotasOp7x6s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cZ/m970x8xnQakjnndvjt6smb1nvYJc4NtACflx+7ll0GiG6xxNxCHCPI7Ko4/BHzpy4sq891A6TYaDSroGlUkRtkcu4SY7vV+X4ybHxzCSK9VsOLHp/g52qGtX++UCts+FobN1z5olMgcdfDfP9uCW5mxQ5udfR+w8yUZbrm5A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SFmuutDn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SFmuutDn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 085051F000E9; Tue, 16 Jun 2026 17:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781631590; bh=JywA4c2ZQw4vIoB8l3YNKtwaOPW7OnJTblxp4A8lBgQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SFmuutDnoxO5vNuzRQ+KMNkJntAEJ0dKWfhX8UZ7dmWBu6qz9dCqWvSselju91Q8r dXxI4PQdL5B+/mWkYiz7+8LmyK39iYulPXh/LKnvwWxUn9Lolca0nGECECbn1KB+TM 88Hbd1Tg0VGxsUDIZ/fpYR14Djezla3p40Medwyo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrew Lunn , Oscar Maes , Alexander Lobakin , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 207/522] pcnet32: stop holding device spin lock during napi_complete_done Date: Tue, 16 Jun 2026 20:25:54 +0530 Message-ID: <20260616145135.748228459@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145125.307082728@linuxfoundation.org> References: <20260616145125.307082728@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oscar Maes [ Upstream commit 73bf3cca7de6a73f53b6a52dc3b1c82ae5667a4d ] napi_complete_done may call gro_flush_normal (though not currently, as GRO is unsupported at the moment), which may result in packet TX. This will eventually result in calling pcnet32_start_xmit - resulting in a deadlock while trying to re-acquire the already locked spin lock. It is safe to split the spinlock block into two, because the hardware registers are still protected from concurrent access, and the two blocks perform unrelated operations that don't need to happen atomically. Fixes: 5b2ec6f2be51 ("pcnet32: use napi_complete_done()") Reviewed-by: Andrew Lunn Signed-off-by: Oscar Maes Reviewed-by: Alexander Lobakin Link: https://patch.msgid.link/20260528140320.5556-1-oscmaes92@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/amd/pcnet32.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/amd/pcnet32.c b/drivers/net/ethernet/amd/pcnet32.c index 72db9f9e7beeae..81cb83caf62a15 100644 --- a/drivers/net/ethernet/amd/pcnet32.c +++ b/drivers/net/ethernet/amd/pcnet32.c @@ -1403,8 +1403,10 @@ static int pcnet32_poll(struct napi_struct *napi, int budget) pcnet32_restart(dev, CSR0_START); netif_wake_queue(dev); } + spin_unlock_irqrestore(&lp->lock, flags); if (work_done < budget && napi_complete_done(napi, work_done)) { + spin_lock_irqsave(&lp->lock, flags); /* clear interrupt masks */ val = lp->a->read_csr(ioaddr, CSR3); val &= 0x00ff; @@ -1412,9 +1414,9 @@ static int pcnet32_poll(struct napi_struct *napi, int budget) /* Set interrupt enable. */ lp->a->write_csr(ioaddr, CSR0, CSR0_INTEN); + spin_unlock_irqrestore(&lp->lock, flags); } - spin_unlock_irqrestore(&lp->lock, flags); return work_done; } -- 2.53.0