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 CB883408626; Mon, 7 Sep 2026 07:05:53 +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=1788764755; cv=none; b=lpeRd27xnG97dj/01jS5JSY8rfx3oRnJHOcTaKulDBtHXvPb1h6N8SCEmA8kVzfvCmIMOgLs7GOzSyd/iluAOXNP85AKPY6JTHonfdXLoHTu6x9WaSQmc5bcWlDvtfoD/wEGGJDOa4u08pqmbh0x9N+oaWpExG9OMI32ryxFG2c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788764755; c=relaxed/simple; bh=9n1YSZo6B3UfOa8vsiem7Bn6ItIGNN4W17gq6R0aCPw=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=GmVarWHpOgHLZWHEPz5aZ1ZOe/huQhicWUuMoJ4uhvboGFVAyviook1vH6dtyVihR+nG/kc632kLTiCJIlViZ+auFsPSFAnxX8qd3ifuWr/SUMw+9SpE5dbSJpKA4jjdfMRDe2pRUHhEpDY4/pWOwxmXiBaCQeDxMyfi/tOTCY0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VrIS4TUI; 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="VrIS4TUI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 275351F00A3A; Mon, 7 Sep 2026 07:05:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788764753; bh=9n1YSZo6B3UfOa8vsiem7Bn6ItIGNN4W17gq6R0aCPw=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=VrIS4TUI/09fxXMy99p5Ci9xSA1YzKtfwoH0Fong9tynQTjvAhizVYQOcrcegCsz8 yZ0guXahXLi3EgYzedgAgDc8nHnECbHB8w0u8davY0cE0S8pfiSoEHBKE7TmBEMyFU dP03+PP215HWarE3j5hCh6wgiCIDzkLS/OtXYatnd+PVwDCaBiYi7n0F0QkJq7ESzt DuP8yrak61g6Cyn+6gGIb8QJPWC2t/aBTRWbL1IaIsdn2yq7NfPkDL5qQgPi7ryiC0 lP92m1TDJiinQLaBIuk7CwqV2w46ZDTZCnfE9TGi0Cha/1lViEYA1vEW6avNweRSzl q2u6nwYT2Acxg== From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 1/3] x86/hyperv: Set irq_retrigger for root partition PCI/MSI irqchip Reply-To: sashiko-reviews@lists.linux.dev To: "Naman Jain" Cc: linux-pci@vger.kernel.org, linux-hyperv@vger.kernel.org In-Reply-To: <20260907065129.269262-2-namjain@linux.microsoft.com> References: <20260907065129.269262-1-namjain@linux.microsoft.com> <20260907065129.269262-2-namjain@linux.microsoft.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 07 Sep 2026 07:05:52 +0000 Message-Id: <20260907070553.275351F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-hyperv@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 > 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/20260907065129.2692= 62-1-namjain@linux.microsoft.com?part=3D1