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Mon, 02 Feb 2026 22:55:10 -0800 (PST) Received: from hu-sumk-hyd.qualcomm.com ([202.46.23.25]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3547b1036e6sm837924a91.11.2026.02.02.22.55.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Feb 2026 22:55:09 -0800 (PST) From: Sumit Kumar Date: Tue, 03 Feb 2026 12:25:01 +0530 Subject: [PATCH 1/2] bus: mhi: ep: Fix potential deadlock in mhi_ep_reset_worker() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260203-reset_worker_deadlock-v1-1-7ed889b5bf19@oss.qualcomm.com> References: <20260203-reset_worker_deadlock-v1-0-7ed889b5bf19@oss.qualcomm.com> In-Reply-To: <20260203-reset_worker_deadlock-v1-0-7ed889b5bf19@oss.qualcomm.com> To: Manivannan Sadhasivam , Alex Elder , Greg Kroah-Hartman Cc: mhi@lists.linux.dev, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Veerabhadrarao Badiganti , Subramanian Ananthanarayanan , Akhil Vinod , Sumit Kumar X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; 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The lock is only needed to protect current MHI state read operation. The lock can be safely released before proceeding with the power up sequence. Fixes: 7a97b6b47353 ("bus: mhi: ep: Add support for handling MHI_RESET") Signed-off-by: Sumit Kumar --- drivers/bus/mhi/ep/main.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c index cdea24e9291959ae0a92487c1b9698dc8164d2f1..73597de373ef7e0c428bcbc126d= 63a9a97f95144 100644 --- a/drivers/bus/mhi/ep/main.c +++ b/drivers/bus/mhi/ep/main.c @@ -1093,6 +1093,7 @@ static void mhi_ep_reset_worker(struct work_struct *w= ork) mhi_ep_mmio_reset(mhi_cntrl); cur_state =3D mhi_cntrl->mhi_state; =20 + mutex_unlock(&mhi_cntrl->state_lock); /* * Only proceed further if the reset is due to SYS_ERR. The host will * issue reset during shutdown also and we don't need to do re-init in @@ -1100,8 +1101,6 @@ static void mhi_ep_reset_worker(struct work_struct *w= ork) */ if (cur_state =3D=3D MHI_STATE_SYS_ERR) mhi_ep_power_up(mhi_cntrl); - - mutex_unlock(&mhi_cntrl->state_lock); } =20 /* --=20 2.34.1