From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794064993; b=LACvPMgPkoOmOT+XIlKrqqQwLLdacsi0hYX1xODnI9JTtfx8ZbHJdhQX6KqifArh9NAD ZH7hqZKm7eFQ0FfNGLKza+gsfcydL7BZV8uhtAO4nCevIqmducSH7T9Zm1kFURnKA0vef NL8A7UvU4Fu8mIhJeIS1S1S8iEZCR76MgBDwwFL+FlEgNaG5oM7rUKhaV9sXs8yPCuNtD OVA9i1OVnpnxYy5Hnty2GGLwIOLWm9MiyjhIMJThVDxHZboF05V1fdjl4cs4pAi9kPih5 LrudwlyTrjI5w9ETAolgWaiD3huXG/Lsqy4CrNVFVHIh2QOUcaz56Ki8/VLGPw0qy4A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794064993; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=Igkqi0cstBGWuyLZGzKiLArIJr40ssOSb/gbjjnMp2I=; b=M3Nrr6VHzEKgHCdNgnZuZeAP8KlapCPs80eKR+3RwvLOmaEJIMYy34MckpqUOTiuZctH YdT9U16LTAhqWEpvCeMZJOPRXVK+xty5HpQ5XI9Yl8gyL0inY8TOCKxqvBJsdoffnkOe3 m1o/dHoTRGEtqWP+QyXgDSLZg1SeA3fFV/qlq46NNqJhTrCV3HBLV32w6EMBrwLr5ffvO RrKCY5AG8DpiBbAafodNhtDGtY5lbIv0GznOfIKkYkJovjFWvD6KkzVhsBlD/UHKL0OXT pvMrsYxwHyMS6IJOUDfDuPl6EDA1io7QjZvtLl7hHSeMbhXm1SMSOl00tOsm8Si2LzA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=mGLeGchR; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 72CC5606A338; Sat, 7 Nov 2026 15:23:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=mGLeGchR Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2195E1F0089F; Sat, 7 Nov 2026 15:23:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794064993; bh=Igkqi0cstBGWuyLZGzKiLArIJr40ssOSb/gbjjnMp2I=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mGLeGchRBw2+lN2WPmuY770+lmvAXat5EB7Tmbxl2MBoJTVm/t7rZ654KyM9siV0+ z0HgSONeNyLghA9SnS+DoYPsXlMoqMax/uz3jnlIss3YnxFjbC23NaBvpc70edXDuN 6c96ObOJ+TJh9RpcgcxdQ5Dp6LJD94VKSy2LIpJY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Matt Turner , Magnus Lindholm , Sasha Levin Subject: [PATCH 7.3 0864/1257] alpha: invalidate the local context in flush_tlb_mm() Date: Sat, 7 Nov 2026 08:52:40 -0500 Message-ID: <20261107135003.189870670@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Magnus Lindholm [ Upstream commit 721bb7a129771f0ff9cef1dd5abfc106ef65feba ] flush_tlb_mm() has the same caller-CPU omission that was fixed in flush_tlb_page(): when the target mm is not the calling CPU's active_mm nothing happens locally, and smp_call_function() handles only the other CPUs, so this CPU may later reuse the old ASN together with the translations it still holds. The active_mm test itself is left alone here. That path calls flush_tlb_current(), which loads a fresh context through __load_new_mm_context() rather than issuing a targeted tbi() against whatever ASN happens to be loaded, so it does not depend on which context is current. The uniprocessor implementation in asm/tlbflush.h already has the missing branch. Counted over a fork-heavy run, flush_tlb_mm() was entered with the mm not this CPU's active_mm 2934 times, and 632 times while otherwise idle. The proposed Alpha hugetlb support routes hugetlb invalidations through flush_tlb_range(), which calls this function. Unmapping or migrating a hugetlb folio from another context will also need this local invalidate. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reviewed-by: Matt Turner Signed-off-by: Magnus Lindholm Link: https://lore.kernel.org/r/20261010142533.974797-8-linmag7@gmail.com Signed-off-by: Magnus Lindholm Signed-off-by: Sasha Levin --- arch/alpha/kernel/smp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c index a5a42ae4a7d80..988e397b0b8a7 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -649,6 +649,9 @@ flush_tlb_mm(struct mm_struct *mm) preempt_enable(); return; } + } else { + /* smp_call_function() does not call back into this CPU. */ + flush_tlb_other(mm); } smp_call_function(ipi_flush_tlb_mm, mm, 1); -- 2.53.0