From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 86FDF442388; Mon, 14 Sep 2026 11:26:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789385167; cv=none; b=V4Rp4yvzNV31C5RJinaEkZCBNAdCBaaIu/XQj8nmQQkDmdLmHZpu2I5wfrnVr0qFPBwZRY86n8DxT/7fcXfkn8RbN0108vSHvmpGfeXVwjkS7F02/+lrKDg+DF9LtLNub/cfcqvRfO2mwwE2/Ar/8L33rH0w5hTjiHi44zhtpjk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789385167; c=relaxed/simple; bh=KKrIHRbTMSmXOXT1z4zqgTdHjLdCwDah4ipih/8s4dI=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=VvVI0foiSkU7EQOnbpr9UUYV81umbvw+FepBWx5hw4GD4v84siax69Hupikh1EdFrX1u23cEmlP2nT3zblN/UvPBHFhLqnuDjW0No02+0qReqdsSfnqGakAtk/2tucyG7A7SPzoXHn2aOrr77CV4dtR1YtF4AC+kgd1TFHUWvwQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ihp4XjN8; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ihp4XjN8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 513711F000FF; Mon, 14 Sep 2026 11:26:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789385166; bh=KKrIHRbTMSmXOXT1z4zqgTdHjLdCwDah4ipih/8s4dI=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Ihp4XjN8utQubM7pPwfenVSyjv1paL152tWC3MBn0CkJw5pLooxFA0Eu8m2zCYue8 EsX4PatfHVd9LAUrC8j0Dwa7fW4DqD4ri5N/N4L7a6/I/pbZfUKh0+jLVpegCX1d78 2jt054e8tKjOIh+hNWhHNr/ohqlicgem1WuxdiGzyZVaaVtolKsBv1gD1rK1/H/3zz ZOisol8QPOrrOGnNNaTR3lskqIIkBZTvfl5V7GhcsYDCsHW2tK3FGltFl0YLqOzTqM 4v2sR5Qw7NxWwWoaBGb9j/Js4Zz8EzWd2xBHkfXM5Nn5huiP7QvlyNWpKdWl7Tc0M1 3WLdFtAfnowNA== From: sashiko-bot@kernel.org Subject: Re: [PATCH v5 1/4] x86/hyperv: Set irq_retrigger for root partition PCI/MSI irqchip Reply-To: sashiko-reviews@lists.linux.dev To: "Naman Jain" Cc: linux-hyperv@vger.kernel.org, linux-pci@vger.kernel.org In-Reply-To: <20260914111836.2119301-2-namjain@linux.microsoft.com> References: <20260914111836.2119301-1-namjain@linux.microsoft.com> <20260914111836.2119301-2-namjain@linux.microsoft.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 14 Sep 2026 11:26:05 +0000 Message-Id: <20260914112606.513711F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > The Hyper-V root partition vPCI MSI irqchip lost its irq_retrigger() > callback when it was converted to msi_create_parent_irq_domain(). The > callback was present on the original irqchip and was dropped during that > conversion. >=20 > On CPU hot-unplug fixup_irqs() migrates the interrupts which are affine to > the outgoing CPU to a new target. If an interrupt still has its pending b= it > set in the outgoing CPU's IRR at that point, fixup_irqs() resends it on t= he > new target through the irqchip's irq_retrigger() callback. As the root > partition PCI/MSI chip no longer provides that callback, the pending > interrupt is silently dropped, which can result in lost interrupts, stalls > and "No irq handler for vector" messages during CPU hotplug. >=20 > Restore irq_chip_retrigger_hierarchy() as the irq_retrigger() callback for > the root partition PCI/MSI irqchip, so that a pending interrupt is resent > on its new target CPU via the parent x86 vector domain. >=20 > Fixes: 4691db0704ac ("x86/hyperv: Switch to msi_create_parent_irq_domain(= )") > Cc: stable@vger.kernel.org > Reviewed-by: Michael Kelley > Reviewed-by: Nam Cao > Signed-off-by: Naman Jain Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260914111836.2119= 301-1-namjain@linux.microsoft.com?part=3D1