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Tue, 10 Nov 2026 19:38:21 -0800 (PST) Received: from pve-server ([49.205.216.49]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1b3b5b2fc09sm23606052c88.10.2026.11.10.19.38.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Nov 2026 19:38:20 -0800 (PST) From: Ritesh Harjani (IBM) To: mdshahid03@gmail.com, maddy@linux.ibm.com Cc: mpe@ellerman.id.au, npiggin@gmail.com, chleroy@kernel.org, sshegde@linux.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Mohammad Shahid Subject: Re: [PATCH] powerpc/perf/vpa-dtl: use GFP_ATOMIC for DTL buffer allocation In-Reply-To: <20261102143719.165508-1-mdshahid03@gmail.com> Date: Wed, 11 Nov 2026 09:04:47 +0530 Message-ID: References: <20261102143719.165508-1-mdshahid03@gmail.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list mdshahid03@gmail.com writes: > From: Mohammad Shahid > > The DTL buffer is allocated while holding dtl_global_lock, which > is spinlock. > > GFP_KERNEL allow direct memory reclaim and may sleep. Combining > GFP_KERNEL with GFP_ATOMIC does not remove the direct reclaim. > > Use GFP_ATOMIC alone to ensure the allocation does not sleep > while the spinlock is held. > > The issue is reported by script coccinelle call_kern.cocci. > > Signed-off-by: Mohammad Shahid This make sense. However we should also add fixes tag and tag stable so it gets backported to stable trees as well. Fixes: 4708fba19ade ("powerpc/vpa_dtl: Add interface to expose vpa dtl counters via perf") Cc: stable@vger.kernel.org LGTM, so feel free to add: Reviewed-by: Ritesh Harjani (IBM)