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 AA84D3AA1A1; Mon, 10 Aug 2026 09:13:02 +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=1786353183; cv=none; b=bYuhgmzcOIKuxzSytgu4ZkUmNpKuYZaSs76zUDl72EDvz4LXU1i4TJfaiuetA3LhrEz0fa4n3X5L/2w7B5RTU3mhWWBLmDtZ15C55q7BzSnxjj876JcPqXnkV38zI+Tp5jzVauKamVskOhFT/Aie6fiEg32UhN0fNbDEkuezvV8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786353183; c=relaxed/simple; bh=F3/7bKz5CDtEx6QZvDHwdM6WrAagl20Tukuy26Y0wvo=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=kyTi6Uat/qWoK2JA4H/09CDSpFAUG+kYzxs0L7QnuFt0xGu2Q4SbiRzvJz0wU2vv/8v24bEIZJyi3tQzDrWzpnBsVy2YDRZ4Grk8yIZ/z+DtDLlR8AnwAqb8Uc39mC0X1bmm+tqeyExa9WLkO11lroDM/zi/diS7NijBn6s0ZWg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FrdxG2kA; 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="FrdxG2kA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0FFE11F000E9; Mon, 10 Aug 2026 09:13:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786353182; bh=F3/7bKz5CDtEx6QZvDHwdM6WrAagl20Tukuy26Y0wvo=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=FrdxG2kAEbPU1HJe2MXuYCqGlMP7cC9/k7Z5x4CKxPbwN4K0k+KbgqViimm7VEPQj dsI9lH7fk4bfVr3nJSOqO5ChBgqeICzNNhoNWha0qa335G1q3psRvHmL4tYr2h7dZ9 npNOI2iVw0qoqizrGrUMb3gm6BFcvpuvHyuHsqzGACWJ3cCd5gLolXwiB3dzUfDVZZ 1WHyw2S7huZK3oPfqn4dp2W+I0hUu1mOfyJ2d4LfU8/+wWhzi5r8q7YjK/AnqwgOEF OivfgQu92W3kJEZa5Uj6cgm7xozR18+tttgPKegeyEofpuXqecImR6MPQOUxhd9YfM Tth1VstBeayyw== From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 1/3] PCI: hv: Set irq_retrigger callback for the Hyper-V 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: <20260810090716.2325295-2-namjain@linux.microsoft.com> References: <20260810090716.2325295-1-namjain@linux.microsoft.com> <20260810090716.2325295-2-namjain@linux.microsoft.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 10 Aug 2026 09:13:01 +0000 Message-Id: <20260810091302.0FFE11F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > The Hyper-V vPCI MSI irqchip never installs an irq_retrigger() callback. >=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 Hyper-V > PCI/MSI chip does not provide 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 > Install irq_chip_retrigger_hierarchy() as the irq_retrigger() callback for > the Hyper-V PCI/MSI irqchip, so that a pending interrupt is resent on its > new target CPU via the parent x86 vector domain. >=20 > Fixes: 4daace0d8ce85 ("PCI: hv: Add paravirtual PCI front-end for Microso= ft Hyper-V VMs") > Cc: stable@vger.kernel.org > Suggested-by: Long Li > Suggested-by: Thomas Gleixner > Reviewed-by: Aditya Garg > Reviewed-by: Shradha Gupta > 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/20260810090716.2325= 295-1-namjain@linux.microsoft.com?part=3D1