From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f178.google.com (mail-pl1-f178.google.com [209.85.214.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E5E825484E for ; Tue, 29 Apr 2025 18:10:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.178 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745950245; cv=none; b=MnZ1bfQ/B95qnNBwY8ry8KIHPwvwzqnUsrMM98vjwiUCEMAQAe+P1dOxFaWTd5xJLACHaEajdmFTadvRoqVJdm3RYzuqasWRufMYmtQ+U+4XYro1XF1UGk1MT1qMSlJgaiSSMKYfYBrYlhw3OsZY6q1ilWoWM7wcGP4HcF49XVo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745950245; c=relaxed/simple; bh=Ziulb9mMltIWQNEALJDPRlCWsnKPBKb9mm4o9Za3zo0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=V4BRCTBK0gk5T2Qd7iNr3acfBK45yfnaiePaKiMcWUzAd2alWCeMGp313Bb3WYItk/1nNZX1Qa/Fx3oIcgjHsmUB9yYqwfIgteeVwRw+iykS8ILkiGwMeS0gLtfoQBiVZerHfQBqMskNucXoDY73bJqs6TQbk6MmnhB7RdHBBcA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=CxNPzkc0; arc=none smtp.client-ip=209.85.214.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CxNPzkc0" Received: by mail-pl1-f178.google.com with SMTP id d9443c01a7336-2240aad70f2so202855ad.0 for ; Tue, 29 Apr 2025 11:10:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1745950243; x=1746555043; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=Ftw/IjMpgU7GPfLzcouQoWIfms9GOb854vnlNb5+taU=; b=CxNPzkc0yqGLiN8vFiDVPlT/B66xGQWeFC04nmxk0exZBDco4A1oVBCVQCAT5yOQ7i YvrbBdf8oCj0s2dDjtBBDfEkBTUegJtilN9LxAerDtrAXLoNCv2wvVRLIr0V+d0+vIbJ wPYzkfMKrmpd19WXpVlqISSZvufk4PZ4W+HUgFKgX+dk3Hc9f4qVMazNf7Sdjry63UFZ 4dYUWGjff04SXA7oinhY8Rh49D9BIbrVelUku4bYyoVzU/Wvk/LBlP8zcWc9rOIIzyE9 RLfSy3vrJjQ9rlNRIT5s4KDlnjIFgf/xB9hlOtQJcz/MPBdhLs9WTJDAQavLeCJKL8P2 QaTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1745950243; x=1746555043; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=Ftw/IjMpgU7GPfLzcouQoWIfms9GOb854vnlNb5+taU=; b=U7+khEDfIO9AsdGM8ygI1+0rxg1S3KQ4ILcVnarDW4JrNvl/Dnuir67Z1s0FYA7ecf tuGm58YSsgEl3tLQWS7QfzCC+G7/Z3G7CrsZ1FO7sVgPUOEtsUAxE7T55/3DgWLgLK8O cIzQX7xq5reykYLGbG4osgcAmHBYNyxKdVNoW2qggIScc6pn19AUpykNBk4AX0ku8w81 2a9BlmLLaarSc6xtXVu6bKebJ/BURsan5qA4Asb9dx/BMkvQC8Rw3c9MzyHAMzkpi4y9 I6kww/pfJ5hlDjyv/97/6lv3jDUMI9rpecP7YWqGOelq0nVySVxpfOGJwW0AfjT0Cg4R eMKg== X-Forwarded-Encrypted: i=1; AJvYcCW5k8NjbuSDhvBrp/N2BfxQnzwkfCEPaZ/s8oKvu3InDY1kOG604+S3h4v3d+4yYLytr4Ph6A==@lists.linux.dev X-Gm-Message-State: AOJu0YxHX0pOWs1SmWajemZ/sy9Blm+RyuxTK5OVc48frQLIaR7oM/ps noUnSKRQ3ZrwerC3G/AcdNvthbW54JcPhjfnDguuINma/A/JsGgHUzsiHy6zVA== X-Gm-Gg: ASbGncuTosBR3fCvuDESAKGL5rDyRlWa8SgTYiaL10nKByMyoZiwTpakiFrboqCUiUe x+0hb/5pLLcs2VMUZQsiETLc5bFNvExXfIytOsWWYIDMLXBrcXZdYpnG4bKRlvRxDvoKyKiY9FG 3jsB2aeOuZgN8nzey/xdHV0Xfchd7Vm/Ospl4I3yjIJV96swRIqWfT1jTBTCAlABkDpGF5qFYID YbR4dARzv9FYIU1f/vGCM8GloKUEBymGbwD8Zk5IOQNCyLNWPUtdo1aTrfUxNqBkmY8Z/Lk1KeF mL7H4Rz9CTAvSCtlagA1dLATdwXEoh3URPMZl0dFzOi+fOS8plGuFzc1LnXNN2DOFWSHctNi X-Google-Smtp-Source: AGHT+IEGtuGPnrFdA7EnAS7AeHO3rAMJ1bXf2n0ATFrXiwa1CPLZUhde5Z8nusKLhSnrBiMW3CwVgA== X-Received: by 2002:a17:902:d486:b0:224:38a:bd39 with SMTP id d9443c01a7336-22df406ab2dmr130415ad.20.1745950242565; Tue, 29 Apr 2025 11:10:42 -0700 (PDT) Received: from google.com (2.210.143.34.bc.googleusercontent.com. [34.143.210.2]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-73e25912efbsm10222670b3a.23.2025.04.29.11.10.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Apr 2025 11:10:42 -0700 (PDT) Date: Tue, 29 Apr 2025 18:10:31 +0000 From: Pranjal Shrivastava To: Nicolin Chen Cc: jgg@nvidia.com, kevin.tian@intel.com, corbet@lwn.net, will@kernel.org, bagasdotme@gmail.com, robin.murphy@arm.com, joro@8bytes.org, thierry.reding@gmail.com, vdumpa@nvidia.com, jonathanh@nvidia.com, shuah@kernel.org, jsnitsel@redhat.com, nathan@kernel.org, peterz@infradead.org, yi.l.liu@intel.com, mshavit@google.com, zhangzekun11@huawei.com, iommu@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org, linux-kselftest@vger.kernel.org, patches@lists.linux.dev, mochs@nvidia.com, alok.a.tiwari@oracle.com, vasant.hegde@amd.com Subject: Re: [PATCH v2 10/22] iommufd/viommmu: Add IOMMUFD_CMD_VCMDQ_ALLOC ioctl Message-ID: References: <094992b874190ffdcf6012104b419c8649b5e4b4.1745646960.git.nicolinc@nvidia.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Apr 29, 2025 at 08:28:01AM +0000, Pranjal Shrivastava wrote: > On Mon, Apr 28, 2025 at 03:44:08PM -0700, Nicolin Chen wrote: > > On Mon, Apr 28, 2025 at 09:34:05PM +0000, Pranjal Shrivastava wrote: > > > On Fri, Apr 25, 2025 at 10:58:05PM -0700, Nicolin Chen wrote: > [...] > > > IIUC, one vintf can have multiple lvcmdqs and looking at the series > > > it looks like the vcmdq_alloc allocates a single lvcmdq. Is the plan to > > > dedicate one lvcmdq to per VM? Which means VMs can share a vintf? > > > > VINTF is a vSMMU instance per SMMU. Each VINTF can have multiple > > LVCMDQs. Each vCMDQ is allocated per IOMMUFD_CMD_VCMDQ_ALLOC. In > > other word, VM can issue multiple IOMMUFD_CMD_VCMDQ_ALLOC calls > > for each VTINF/vSMMU. > > > > Ack. I'm just wondering why would a single VM want more than one vCMDQ > per vSMMU? > [...] I guess the only thing on this patch from me was to understand why would a single VM want more than one vCMDQ per vSMMU? (Just curious to know :) ) Apart from that, Reviewed-by: Pranjal Shrivastava > > > Thanks > > Nicolin > Thanks, Praan