From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 334494685; Wed, 13 Aug 2025 00:41:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755045682; cv=none; b=lvRL13G2xSmx8G/BLpak14c9ailqxJi/gmCj0faPZuaAM//ZdMJ6vodPCx7KwuQmW235I66zgBeNdVQJlaiXVTD97amWfGUtRkm27Vnzkdti5U/s/WkCYXZPzg178AbQTqs7fyAH+djlD9k/8oHFrLk7uD7WKfCfROy1aJf3jdA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755045682; c=relaxed/simple; bh=Asl961UA0vCD59+9K43qgi5UO6CxgMvHPUzfukUNK24=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Om9OxuIk++tU38ug3SFRPGCnn2FeNoIjGcTu7UhNY+s9mlpF3mgbcerr0DkGDF4YMjckXaMATmf0ufZxKadsjSpG5oksgXD6FJpNYq3NFGskVVQUPDAl57VlhSwChLzbBTKBszRSZ6F9+IBaM8Sed3qzmDuG2zrhKrqzoaQ+sEI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vJ2ozjWN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vJ2ozjWN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6494EC4CEF0; Wed, 13 Aug 2025 00:41:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755045681; bh=Asl961UA0vCD59+9K43qgi5UO6CxgMvHPUzfukUNK24=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vJ2ozjWNphL/gaj64VX0kduHHYvtCg2wG0Qn1q3Eo0znTTQEWAb7/AOGep3z0Afpo 2Ay2/hE0Eat3ioXCuCl6mg+l4mPD5Cdm0nZWz3GD/hCRYkKNDZ3rljqXggql5iwbZf 1hVf5D8ri+rTQP5fZazAfYv5ekrFw2AU7VisIoC6uXj9LfRbm97O2FG/TVyUsrrHr7 JWeqWldHB6kDW/RJtaDuAj31lbtkfzSWJNwsnsiXTgEnUDo+ByfLSY8/uvfv7rq9R4 aopPNxNNxDvb0DHs9jVxWOn/+cn01wb99WAyxwjslCZNBsa7DAx1/mdum2jyEiUTvE 4dlMG1OOwjRSw== Date: Wed, 13 Aug 2025 00:41:20 +0000 From: Wei Liu To: Nuno Das Neves Cc: mhklinux@outlook.com, kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, lpieralisi@kernel.org, kw@linux.com, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, x86@kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [PATCH v4 2/7] x86/hyperv: Use hv_setup_*() to set up hypercall arguments -- part 1 Message-ID: References: <20250718045545.517620-1-mhklinux@outlook.com> <20250718045545.517620-3-mhklinux@outlook.com> <252e58be-4377-49b7-a572-0d40f54993d1@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <252e58be-4377-49b7-a572-0d40f54993d1@linux.microsoft.com> On Tue, Aug 12, 2025 at 05:22:29PM -0700, Nuno Das Neves wrote: > On 7/17/2025 11:55 PM, mhkelley58@gmail.com wrote: > > From: Michael Kelley > > > > Update hypercall call sites to use the new hv_setup_*() functions > > to set up hypercall arguments. Since these functions zero the > > fixed portion of input memory, remove now redundant calls to memset() > > and explicit zero'ing of input fields. > > > > Signed-off-by: Michael Kelley > > Reviewed-by: Nuno Das Neves > > --- > > > > Notes: > > Changes in v4: > > * Rename hv_hvcall_*() functions to hv_setup_*() [Easwar Hariharan] > > * Rename hv_hvcall_in_batch_size() to hv_get_input_batch_size() > > [Easwar Hariharan] > > > > Changes in v2: > > * Fixed get_vtl() and hv_vtl_apicid_to_vp_id() to properly treat the input > > and output arguments as arrays [Nuno Das Neves] > > * Enhanced __send_ipi_mask_ex() and hv_map_interrupt() to check the number > > of computed banks in the hv_vpset against the batch_size. Since an > > hv_vpset currently represents a maximum of 4096 CPUs, the hv_vpset size > > does not exceed 512 bytes and there should always be sufficent space. But > > do the check just in case something changes. [Nuno Das Neves] > > > > > > > diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c > > index 090f5ac9f492..87ebe43f58cf 100644 > > --- a/arch/x86/hyperv/irqdomain.c > > +++ b/arch/x86/hyperv/irqdomain.c > > @@ -21,15 +21,15 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level, > > struct hv_device_interrupt_descriptor *intr_desc; > > unsigned long flags; > > u64 status; > > - int nr_bank, var_size; > > + int batch_size, nr_bank, var_size; > > > > local_irq_save(flags); > > > > - input = *this_cpu_ptr(hyperv_pcpu_input_arg); > > - output = *this_cpu_ptr(hyperv_pcpu_output_arg); > > + batch_size = hv_setup_inout_array(&input, sizeof(*input), > > + sizeof(input->interrupt_descriptor.target.vp_set.bank_contents[0]), > > + &output, sizeof(*output), 0); > > > > Hi Michael, I finally managed to test this series on (nested) root > partition and encountered an issue when I applied this patch. > > With the above change, I saw HV_STATUS_INVALID_ALIGNMENT from this > hypercall. I printed out the addresses and sizes and everything looked > correct. The output seemed to be correctly placed at the end of the > percpu page. E.g. if input was allocated at an address ending in 0x3000, > output would be at 0x3ff0, because hv_output_map_device_interrupt is > 0x10 bytes in size. > > But it turns out, the definition for hv_output_map_device_interrupt > is out of date (or was never correct)! It should be: > > struct hv_output_map_device_interrupt { > struct hv_interrupt_entry interrupt_entry; > u64 extended_status_deprecated[5]; > } __packed; > > (The "extended_status_deprecated" field is missing in the current code.) > > Due to this, when the hypervisor validates the hypercall input/output, > it sees that output is going across a page boundary, because it knows > sizeof(hv_output_map_device_interrupt) is actually 0x58. > > I confirmed that adding the "extended_status_deprecated" field fixes the > issue. That should be fixed either as part of this patch or an additional > one. Thanks for testing this, Nuno. In that case, can you please submit a patch for hv_output_map_device_interrupt? That can go in via the fixes tree. Thanks, Wei > > Nuno > > PS. I have yet to test the mshv driver changes in patch 6, I'll try to > do so this week. > > > intr_desc = &input->interrupt_descriptor; > > - memset(input, 0, sizeof(*input)); > > input->partition_id = hv_current_partition_id; > > input->device_id = device_id.as_uint64; > > intr_desc->interrupt_type = HV_X64_INTERRUPT_TYPE_FIXED; > > @@ -41,7 +41,6 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level, > > else > > intr_desc->trigger_mode = HV_INTERRUPT_TRIGGER_MODE_EDGE; > > > > - intr_desc->target.vp_set.valid_bank_mask = 0; > > intr_desc->target.vp_set.format = HV_GENERIC_SET_SPARSE_4K; > > nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), cpumask_of(cpu)); > > if (nr_bank < 0) { > > @@ -49,6 +48,11 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level, > > pr_err("%s: unable to generate VP set\n", __func__); > > return -EINVAL; > > } > > + if (nr_bank > batch_size) { > > + local_irq_restore(flags); > > + pr_err("%s: nr_bank too large\n", __func__); > > + return -EINVAL; > > + } > > intr_desc->target.flags = HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET; > > > > /* > > @@ -78,9 +82,8 @@ static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry) > > u64 status; > > > > local_irq_save(flags); > > - input = *this_cpu_ptr(hyperv_pcpu_input_arg); > > > > - memset(input, 0, sizeof(*input)); > > + hv_setup_in(&input, sizeof(*input)); > > intr_entry = &input->interrupt_entry; > > input->partition_id = hv_current_partition_id; > > input->device_id = id; > >