From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.208.50 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793976208; b=Iy+LMvh/NYk/7ULarJpQSSCM3zh6QviVWQJbQBtms02sfuLNMbJyOMpvfCjWpEwc78YW mqb+Sz4gBlCADyyALiFhDjl37YBIJs8VfQEaLm2U7Cr1eUhEINAmPDwwRcJpd68s70Ghf 3pBv1N+rGU6+7kEY6UakXBehxG6WRic98GOoR4D1c6NJ7C8RE0sA4MUs+EAieCTQKdlXn AhoZB/qPzWPGIsQpuFlCQvxLlTOkABCdI+OY93SlYpLriVWW2nnQt7pBmuzwXPO2EZ1VL IifoPqzQM3UaU2Fd6xUqlHV51IDcyzZdCpGWeLc9EppgGoGfYBc8ePmHKVzrf8LPZGQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793976208; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:X-Google-Original-From:Date:To:Cc:Subject:Message-ID:References: MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=1coO61O9o20KGfWhe+U/6TV0ZY/FeV096v+PDZIBmoM=; b=n7HFgJbxawi3kL0QGx814wtYuOM4m9Dt/Pk+GC0UZXWwpnGCQCPjH9t34Ev1NV7N2YDe DRKJSlsRoOAF2Gnstb0w0UEiDlVw28a9DvzrreXiSBKgL2jLdu4w/SYGYjuzgDoHbE0mq ZQ+v/L2ConZjB65cODyJt3tQZVk0cfEWfc3vOPfCZw66kods8aQJ05BYVLh3V3jwdh33w 5UO3GMr/WmyHLN+Footzwu3N7SzCRvOw5/b+9hRvLSR1wSZ+ZZOWBJC3+m66MuIUY5sZ0 /wHqxsc0HpKiRqTUndcpCOztfopSRNn8uQLQE4asCenuMmNTZ490JWjUsCOAQp+5L5g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=dQ8Kjz3P; arc=none smtp.remote-ip=209.85.208.50 Received: from mail-ed1-f50.google.com (mail-ed1-f50.google.com [209.85.208.50]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8243E606EEBB for ; Fri, 6 Nov 2026 14:43:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 8243E606EEBB Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=dQ8Kjz3P Received: by mail-ed1-f50.google.com with SMTP id 4fb4d7f45d1cf-6b58cb69927so2170934a12.0 for ; Fri, 06 Nov 2026 06:43:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1793976206; x=1794581006; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:date:from:from:to:cc:subject :date:message-id:reply-to:content-type; bh=1coO61O9o20KGfWhe+U/6TV0ZY/FeV096v+PDZIBmoM=; b=dQ8Kjz3Pm/40Y6QK+wnykiNHDgz7dKP607sj6/+hqieIq1ZmyilklclOYXjWaBJyZQ wigV9r8VouxbEKE9QgPdw1VpSrB3xLnotHYSSNbzuz878AnRPuvoVHRTNcqgEq7hLDnq EBy4H5xYRegGJoTvMOlxOYRVq93ULaPKtOQBRtm4a5TxD5b5qxrLBPFkjRnIHAg/fRo8 SPdaU35rkr0LfaG3/AS4/PMkK2BSbubxBavooY3Ygux0TcvwzrklGLkuYTCBblRoq/9Q wGBWvVpbu/YmDkyrFWrcQ9+Xr/vMo02AxG7ipmZa006A9g2kUtdIwncG4kcQ9DAOguTO Q3Kw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1793976206; x=1794581006; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:date:from:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=1coO61O9o20KGfWhe+U/6TV0ZY/FeV096v+PDZIBmoM=; b=hvxLS9lwvLzM2ObKseEj1dy686GEi9K7HWzrHKMMIUtsM2IbhDf0RhJg4I0BPS4j8X Ae9bxxIxvBzPbBmAg4/LeRZOhkjTaZMvPQtNJpADKaRzHQViEGSDxL0AzEWpTQy5Bgbu W+/VLe0jGSK1I42VL52v6oWLssccuH5jEa34yV8DXVNs8JrbTrsD2KtYYPYkuLi7lUMj 0RC7N+JDnI/yGRylScHY2uDArObVE6oWZr7YX+cVT1eMtowptxq4NeL6WjBj9+OfWlyK lxaLXmg3AF7W9awQbwbpEhSz8RcjypU+WvH7EEGlX8ObPe/mR4U+2/hN3cD9xJ4gvhlI gZ+g== X-Forwarded-Encrypted: i=1; AKwUvBxHSG8Wgu2Xf5Tlibqu9sNbUvWgG0GdL5kKCL4op3PZ6G+46Uzp5ucybEB75vGi3uSYqOwEoTh6k6KQnEY=@vger.kernel.org X-Gm-Message-State: APuU4Z9FNXDyR6KYEV/XjyCP74gN+k5aRJOYaBx5fIj4yY0AdsepoUIO SvMFoALdT+3UFXiswIJgnoOqRdPmxm7Nj7xGi7uGqsmZusFR3baX9Knm X-Gm-Gg: AYBFou2ZTnuNO71yll0OmBJ0FPpFGB9RaiNDXt+GUWmFLx8/Kl6EcMA0RoWZbKSRkKk YEjuapZwJ2PbTHypqBwrK84uNYoUPfjkPdzkEmwefp/+m+/DHeZPD1jR+CjfxCyDfncieFeuGyn a2qBWxRbN3AJuW88EzFmER2nZ/j8vn5DEQ8sqh3hJ48QaQuRTI8P9MnjEx4wxRMjfdGoqscTr5I Nhmuy4hkvxks7p7cI1CiougRDxEfF2eJLTnqLium0W39Xlpde5brPx3U/TqiwOyelXMTLochr92 XEtrJIGv/HD2zTPBlOTdOyh9gGMMI/irSz9BZwmnRyNAzSTu6RxwB17O77r6rBfOBpgM9BZrCy+ 3405FaGq+A70Vzrhx1hZ6oA/sF6y5XdM0lrOmnMBjBXxLEsiMx6PTCLtmuKsFT3R2OrkmTg0JxH XsiflrQ/SXgvrlXbmvTv5B/nMejWsdeH7Fg5G6bDijNe5Ky9j8efLyqhMxoLPR78zaU2BRR1yBs fENISX76ty4eI2GIgCgZpWPL9mjMMDSERzN42f2ZGlvZdKW+osB4hvUf0IwSSXx6e6+ X-Received: by 2002:a17:907:fdcb:b0:c2e:616b:6763 with SMTP id a640c23a62f3a-c4d3525a3f4mr249438666b.3.1793976205728; Fri, 06 Nov 2026 06:43:25 -0800 (PST) Received: from milan ([2001:9b1:d5a0:a500::24b]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c4d35631eb2sm86304166b.27.2026.11.06.06.43.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Nov 2026 06:43:24 -0800 (PST) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Fri, 6 Nov 2026 15:43:21 +0100 To: Linus Torvalds Cc: Uladzislau Rezki , Herbert Xu , "Liam R. Howlett (Google)" , Davidlohr Bueso , Michal Hocko , Baoquan He , Alexander Potapenko , Andrey Ryabinin , Marco Elver , Michal Hocko , Linux Crypto Mailing List , Andrew Morton , Thomas Graf , linux-mm@kvack.org, linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org, Lorenzo Stoakes , Chris Mason , Alice Ryhl , Andrew Ballance , stable@vger.kernel.org, "David Hildenbrand (Arm)" Subject: Re: [PATCH 4/4] rhashtable: fix vmalloc() deadlock in atomic rehash Message-ID: References: X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Nov 05, 2026 at 01:02:35PM -0800, Linus Torvalds wrote: > On Thu, 5 Nov 2026 at 10:44, Uladzislau Rezki wrote: > > > > @@ -1025,7 +1025,13 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source, > > } > > } > > } else { > > - spin_lock(&br->hash_lock); > > + if (in_serving_softirq()) { > > + if (!spin_trylock(&br->hash_lock)) > > I don't think that in_serving_softirq() makes any sense. > > If I read this code correctly - and it's possible I didn't - this is > always called under local_bh_disable(). > > And local_bh_disable() will have increased the preempt-count exactly > so that it looks like it's in_serving_softirq(). > Sorry, probably i am missing something here. My understanding is that local_bh_disable() adds SOFTIRQ_DISABLE_OFFSET and in_serving_softirq() checks another SOFTIRQ_OFFSET bit. -- Uladzislau Rezki