From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6BA491C69D for ; Tue, 17 Mar 2026 12:04:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773749091; cv=none; b=CGOo+SvRqh5yRtFkea50H7cHwTZh7jmDKwJ6npGlo1Fne8bT2NaSLeF+WfpxzwGArpYsz+sgj5ILpQum43x6L7Op4mWJoXlpvUw6l4Ks65Jd28/rcxE5fKRxc/wmlSFoWLpMW8LWB6ws4C4dNDek/cvC2zn4DZEYm1+HWWQ5vys= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773749091; c=relaxed/simple; bh=UF93AMDU934PfoUl4pCSFdj/AiHxFe/BJOM8cxjD04k=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=sXM6s2/TnPe6+wL4MuKL/kD9/khHy6ifgoVBBo8iucu+VIhv+Ja3EPULgTAXdMElk2s12FK+qaCyvyR/fQWExo2feDiZjMQeRVQn2Qnzk2s9d+loacusuOIe/gqFmhOooBXzTy1/tZMGKAcuE9TG3DeVFm6nrKQX876ckv2GqaE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=F+/eoHBr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="F+/eoHBr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 86B2AC4CEF7; Tue, 17 Mar 2026 12:04:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773749091; bh=UF93AMDU934PfoUl4pCSFdj/AiHxFe/BJOM8cxjD04k=; h=Subject:To:Cc:From:Date:From; b=F+/eoHBrXEfBDT1jvlcAhhrV+iPwQcT7hpslqKVVslKuXQ9IndOjPRUtcM5e1DXc5 4IjfzBuQ8BIpKaelMy7AtAqM4mO/4+Ti5kfzL+lZ8szl9hYosWzONbuBCfIS3UH6Mm rNpbdg8SqpP7EB0l5a1gnCAm5a4bHqbkd+Nmu0LQ= Subject: FAILED: patch "[PATCH] s390/stackleak: Fix __stackleak_poison() inline assembly" failed to apply to 6.6-stable tree To: hca@linux.ibm.com,gor@linux.ibm.com Cc: From: Date: Tue, 17 Mar 2026 13:04:39 +0100 Message-ID: <2026031739-hankie-exceeding-ac13@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 674c5ff0f440a051ebf299d29a4c013133d81a65 # git commit -s git send-email --to '' --in-reply-to '2026031739-hankie-exceeding-ac13@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 674c5ff0f440a051ebf299d29a4c013133d81a65 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 2 Mar 2026 14:35:00 +0100 Subject: [PATCH] s390/stackleak: Fix __stackleak_poison() inline assembly constraint The __stackleak_poison() inline assembly comes with a "count" operand where the "d" constraint is used. "count" is used with the exrl instruction and "d" means that the compiler may allocate any register from 0 to 15. If the compiler would allocate register 0 then the exrl instruction would not or the value of "count" into the executed instruction - resulting in a stackframe which is only partially poisoned. Use the correct "a" constraint, which excludes register 0 from register allocation. Fixes: 2a405f6bb3a5 ("s390/stackleak: provide fast __stackleak_poison() implementation") Cc: stable@vger.kernel.org Signed-off-by: Heiko Carstens Reviewed-by: Vasily Gorbik Link: https://lore.kernel.org/r/20260302133500.1560531-4-hca@linux.ibm.com Signed-off-by: Vasily Gorbik diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index cc187afa07b3..78195ee5e99f 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -159,7 +159,7 @@ static __always_inline void __stackleak_poison(unsigned long erase_low, " j 4f\n" "3: mvc 8(1,%[addr]),0(%[addr])\n" "4:" - : [addr] "+&a" (erase_low), [count] "+&d" (count), [tmp] "=&a" (tmp) + : [addr] "+&a" (erase_low), [count] "+&a" (count), [tmp] "=&a" (tmp) : [poison] "d" (poison) : "memory", "cc" );