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Mon, 18 May 2026 08:08:53 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay07.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 64I88oLF47448476 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 18 May 2026 08:08:50 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1866E20043; Mon, 18 May 2026 08:08:50 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 61A5120040; Mon, 18 May 2026 08:08:48 +0000 (GMT) Received: from [9.123.5.233] (unknown [9.123.5.233]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 18 May 2026 08:08:48 +0000 (GMT) Message-ID: <0c6d2855-61df-4fd2-bede-0c204f4fd2b1@linux.ibm.com> Date: Mon, 18 May 2026 13:38:33 +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 0/3] powerpc: fix preempt_count imbalances in perf and kexec paths To: Aboorva Devarajan , Madhavan Srinivasan , linuxppc-dev@lists.ozlabs.org Cc: Athira Rajeev , Christophe Leroy , linux-kernel@vger.kernel.org, Sourabh Jain , Ritesh Harjani References: <20260518050855.1147242-1-aboorvad@linux.ibm.com> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: <20260518050855.1147242-1-aboorvad@linux.ibm.com> Content-Type: text/plain; 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These are get_cpu/put_cpu and > get_cpu_var/put_cpu_var pairing errors that leave preempt_count > incorrectly elevated or underflowed. > Thanks for fixing some of these. while we do this, Can you fix these mismatch in preempt disable/enable in below files as well. 1. kernel/kprobes.c - kprobe_handler - Does disable, but doesn't enable in some return paths. A definite leak. 2. Maybe platforms/pseries/lpar.c and platforms/powernv/opal-tracepoints.c. In __trace_hcall_entry/exit. It maybe a very corner case, I don't see a big concern there. But it may be remotely possible. Need to evaluate whether it should be fixed or not.