From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DD3DCCA0FED for ; Fri, 5 Sep 2025 07:13:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:Cc:To:From: Subject:Message-ID:References:Mime-Version:In-Reply-To:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3udnh9xsllR+FkjIGPPOo5bX8r6scLid4vmBPD5wmTc=; b=cUj5Emcuuv+4zqvwT6Ge8lEsT3 ReDIrPN3+vcoGKpO9xUv95VWbIe+2Mqi3VX0XV8tWa6RN+jK5rzCvy7qXkJqZZJRttPed6ajCh3aI jVTJZRjRw+J8jfj6cx/zRQ+H7GBHAfjiYAWxFxkc8Vq0V9vgt4MQyt8Id1ipmCIFDcYxdoWdaUP9P h3/ipibkt+9yIkyXL/DTgaKxB2NQo4Xl0eUrO/+rv+irLqQrjmMbDh85Pc7ccnlFq84ubdcsUycam dwXpLA1x19XMwkM7oRrBDvWnsKimPWUKRad5y+k7eDWein9mU2bEkKxGYlhjtHL8zSuMRo8hYCFh3 EJDzVAiQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuQdl-0000000HW8W-0uMl; Fri, 05 Sep 2025 07:13:45 +0000 Received: from mail-pj1-x1049.google.com ([2607:f8b0:4864:20::1049]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuPAo-0000000H3Or-1Oyo for linux-arm-kernel@lists.infradead.org; Fri, 05 Sep 2025 05:39:47 +0000 Received: by mail-pj1-x1049.google.com with SMTP id 98e67ed59e1d1-329745d6960so1718123a91.0 for ; Thu, 04 Sep 2025 22:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1757050785; x=1757655585; darn=lists.infradead.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=3udnh9xsllR+FkjIGPPOo5bX8r6scLid4vmBPD5wmTc=; b=zUWO50D3tiM87PviUcIZeXZHpRKLACZowq5urDeMUufJe8NTS2KuH/gppho7SKIqB7 /YDJ3u8WlYU1zM4jUFyGgoVfLQpLFb08dx52N5maIYS6IO9D9wbmbe+3GdUwX8FNZkzV pYeFDn1PCbPTllXIxPJp7TOlhXBXh7ImatvaQmAIvjSkC7uyQ3mWlVPQ3ztuwXv10cbR zckgjoyAK213NOjrtVVukE0PgNXdiViELF1ErH6ej+YJkkWOz7a+5IVQHAe4eSqlGfAi 7NRFLmJePAh6dTzGii8rnF//Kdn5f1ChyJzke/YMVQPkTQ356Gc7GcgmLLRBVNTkd2fn Ob/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1757050785; x=1757655585; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=3udnh9xsllR+FkjIGPPOo5bX8r6scLid4vmBPD5wmTc=; b=U4Hhuei8YE+iUDR//N+Qt8sp85yU6uAjgGXSnlqG/FDQYswr6Da3LxGFZVJjKv2KVl rNTk2Skop94JW+W4DwzV7e0jeu4QK0JbZ/oygGA00cczRLNUgN7t48p7n4wwVWRSE5dV muzuGQjz4HgAbQyO/QcQl16pAHmLVKEItNDa2nYsgGIiRMLMHZSkN1JNG7PmFv7cBjYG 31SytEEAfw6H6/hSkUYjFuQdr8rvDQsreCI9qlNJgEcOPAuXB3c6a3jvRBBvTjLWvM5c P2EYfDubq6Dr8ogoHeUCO2dcMYHZnoxMYZ11DwuyOpKsN/b2HLWrKJLXE8ITFS2MDVRM b2nw== X-Forwarded-Encrypted: i=1; AJvYcCW3s/6Rs/TKXvLG9BUEBaC8iPcvSXdqRfJMvEoFIwcYA/+1cgxKxbXqsQvndKLv5vyZUsWiT0W5mAICvcy5BUBI@lists.infradead.org X-Gm-Message-State: AOJu0YxYvNhTq0Z+aNOMao5d0Yt14bY/qYbvFS7GfCbKoVHye4PFNrXH boJbUF6VYCSGh7zqMtgkLl8xq3rnrFcR61/UFgV7LncLNKIbZu80LQZFRubolRAW7VXio5/4G5z 4BmMDJg== X-Google-Smtp-Source: AGHT+IEl3aDxdJxOeFOgsIqqYfLRUExl039yXm0dtHzzby5zYzVGU35ZbpW1dVjZIdU0C50mCLd9IUYMCJw= X-Received: from pjuw15.prod.google.com ([2002:a17:90a:d60f:b0:325:5e4e:4bd4]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3809:b0:329:dff0:701b with SMTP id 98e67ed59e1d1-329dff070c6mr19066965a91.17.1757050784899; Thu, 04 Sep 2025 22:39:44 -0700 (PDT) Date: Thu, 4 Sep 2025 22:39:37 -0700 In-Reply-To: Mime-Version: 1.0 References: <20250828000156.23389-1-seanjc@google.com> Message-ID: Subject: Re: [PATCH v2 0/7] Drivers: hv: Fix NEED_RESCHED_LAZY and use common APIs From: Sean Christopherson To: Wei Liu Cc: Marc Zyngier , Oliver Upton , Catalin Marinas , Will Deacon , Tianrui Zhao , Bibo Mao , Huacai Chen , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "K. Y. Srinivasan" , Haiyang Zhang , Dexuan Cui , Peter Zijlstra , Andy Lutomirski , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-hyperv@vger.kernel.org, rcu@vger.kernel.org, Nuno Das Neves , Mukesh R Content-Type: text/plain; charset="us-ascii" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250904_223946_375538_DC1142AE X-CRM114-Status: GOOD ( 32.05 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Sep 04, 2025, Wei Liu wrote: > On Wed, Aug 27, 2025 at 05:01:49PM -0700, Sean Christopherson wrote: > > Fix a bug where MSHV root partitions (and upper-level VTL code) don't honor > > NEED_RESCHED_LAZY, and then deduplicate the TIF related MSHV code by turning > > the "kvm" entry APIs into more generic "virt" APIs. > > > > This version is based on > > > > git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git hyperv-next > > > > in order to pickup the VTL changes that are queued for 6.18. I also > > squashed the NEED_RESCHED_LAZY fixes for root and VTL modes into a single > > patch, as it should be easy/straightforward to drop the VTL change as needed > > if we want this in 6.17 or earlier. > > > > That effectively means the full series is dependent on the VTL changes being > > fully merged for 6.18. But I think that's ok as it's really only the MSHV > > changes that have any urgency whatsoever, and I assume that Microsoft is > > the only user that truly cares about the MSHV root fix. I.e. if the whole > > thing gets delayed, I think it's only the Hyper-V folks that are impacted. > > > > I have no preference what tree this goes through, or when, and can respin > > and/or split as needed. > > > > As with v1, the Hyper-V stuff and non-x86 architectures are compile-tested > > only. > > > > v2: > > - Rebase on hyperv-next. > > - Fix and converge the VTL code as well. [Peter, Nuno] > > > > v1: https://lore.kernel.org/all/20250825200622.3759571-1-seanjc@google.com > > > > I dropped the mshv_vtl changes in this series and applied the rest > (including the KVM changes) to hyperv-next. mshv_do_pre_guest_mode_work() ended up getting left behind since its removal was in the last mshv_vtl patch. $ git grep mshv_do_pre_guest_mode_work drivers/hv/mshv.h:int mshv_do_pre_guest_mode_work(ulong th_flags); drivers/hv/mshv_common.c:int mshv_do_pre_guest_mode_work(ulong th_flags) drivers/hv/mshv_common.c:EXPORT_SYMBOL_GPL(mshv_do_pre_guest_mode_work); Want to squash this into 3786d7d6b3c0 ("mshv: Use common "entry virt" APIs to do work in root before running guest")? --- drivers/hv/mshv.h | 2 -- drivers/hv/mshv_common.c | 22 ---------------------- 2 files changed, 24 deletions(-) diff --git a/drivers/hv/mshv.h b/drivers/hv/mshv.h index 0340a67acd0a..d4813df92b9c 100644 --- a/drivers/hv/mshv.h +++ b/drivers/hv/mshv.h @@ -25,6 +25,4 @@ int hv_call_set_vp_registers(u32 vp_index, u64 partition_id, u16 count, int hv_call_get_partition_property(u64 partition_id, u64 property_code, u64 *property_value); -int mshv_do_pre_guest_mode_work(ulong th_flags); - #endif /* _MSHV_H */ diff --git a/drivers/hv/mshv_common.c b/drivers/hv/mshv_common.c index eb3df3e296bb..aa2be51979fd 100644 --- a/drivers/hv/mshv_common.c +++ b/drivers/hv/mshv_common.c @@ -138,25 +138,3 @@ int hv_call_get_partition_property(u64 partition_id, return 0; } EXPORT_SYMBOL_GPL(hv_call_get_partition_property); - -/* - * Handle any pre-processing before going into the guest mode on this cpu, most - * notably call schedule(). Must be invoked with both preemption and - * interrupts enabled. - * - * Returns: 0 on success, -errno on error. - */ -int mshv_do_pre_guest_mode_work(ulong th_flags) -{ - if (th_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) - return -EINTR; - - if (th_flags & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) - schedule(); - - if (th_flags & _TIF_NOTIFY_RESUME) - resume_user_mode_work(NULL); - - return 0; -} -EXPORT_SYMBOL_GPL(mshv_do_pre_guest_mode_work); base-commit: 3786d7d6b3c0a412ebe4439ba4a7d4b0e27d9a12 --