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Thu, 14 May 2026 05:24:13 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay06.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 64E5O9Ih29229502 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 May 2026 05:24:09 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 964832004B; Thu, 14 May 2026 05:24:09 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0281520040; Thu, 14 May 2026 05:24:08 +0000 (GMT) Received: from [9.123.5.233] (unknown [9.123.5.233]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Thu, 14 May 2026 05:24:07 +0000 (GMT) Message-ID: <60e44383-0791-4d0a-8c16-41fb4f436e0b@linux.ibm.com> Date: Thu, 14 May 2026 10:54:07 +0530 X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] powerpc/hv-gpci: fix preempt count leak in sysfs show paths To: "Ritesh Harjani (IBM)" Cc: Christophe Leroy , Kajol Jain , linux-kernel@vger.kernel.org, Aboorva Devarajan , Madhavan Srinivasan , Athira Rajeev , linuxppc-dev@lists.ozlabs.org References: <20260508041256.3447113-1-aboorvad@linux.ibm.com> <5x4usp43.ritesh.list@gmail.com> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: <5x4usp43.ritesh.list@gmail.com> Content-Type: text/plain; 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It will be nice to have some mechanism to catch > these error handling paths where preempt counts might be getting leaked. > There is CONFIG_DEBUG_PREEMPT=y which helps you to catch these issue where count leak happens. Otherwise we only see end result, but not the culprit. That said, we do have issues of not nesting with get_cpu/put_cpu in few places and preempt_disable/preempt_enable in few return paths still.