Re: [RFC] Significant Random I/O Performance Regression in Linux Kernel 6.18 (Up to 27.7%) Likely Caused by Commit 3c7ac40d7322

Bart Van Assche <[email protected]> Fri, 10 Jul 2026 07:56:23 -0700

Newsgroups	org.kernel.vger.linux-samsung-soc,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-kernel,org.kernel.vger.linux-scsi,org.kernel.vger.stable
Message-ID	<[email protected]>

On 7/10/26 12:17 AM, 孙魁 (Kui Sun) wrote:
> Through investigation, we identified that upstream commit
> 3c7ac40d732232fec0ba31d0a5e3cc9c112fc2e7, merged in April 2025, is
> likely responsible for this performance drop.
Two fixes for that commit are present in the upstream kernel. Are these
fixes present in your kernel tree?

commit eabcac808ca3ee9878223d4b49b750979029016b
Author: Bart Van Assche <[email protected]>
Date:   Fri Aug 15 08:58:23 2025 -0700

     scsi: ufs: core: Fix IRQ lock inversion for the SCSI host lock

commit 034d319c8899e8c5c0a35c6692c7fc7e8c12c374
Author: Nitin Rawat <[email protected]>
Date:   Tue Jul 29 04:27:11 2025 +0530

     scsi: ufs: core: Fix interrupt handling for MCQ Mode

Thanks,

Bart.