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 C7AB3CA0EFF for ; Thu, 28 Aug 2025 00:07:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To: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: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=vhbQgqknyAyVeKaXs8kP6grJ1hrwQUkSmJiE25IRpuQ=; b=YlGpBKRxCxC6lKWQUQ1N4F9xrC ua/9OYrPTEf4Gow9ZK2NQtTkHj/uA1ikrSxV4KMn7ZTLLtFo6zZCzFQUmeXNZ7Sf4rdJH0ypntsnY FcDeQWgIw7c6OYwC1+7DPe/CXdpCoqSTRbDB2VumWzGBxR61jBhtRTmXtpQhMLuvNjzmsrpjswa48 zviO/jJ7lTgign+syp4X9drp+e8rX0q6TOsSGewGNn1J+XZIlpf4Dp7HnWu3o9gpC0RdKmbovUk7u p+8Pfd1cCCA49qyD0o3sL2tdukVEk/usWGppoA7oOzP7ooDNYxOt+yfwaks316RMK3tJwJiYsfvli VgzP020w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1urQBB-0000000HJZf-1HdK; Thu, 28 Aug 2025 00:07:49 +0000 Received: from mail-pf1-x44a.google.com ([2607:f8b0:4864:20::44a]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1urQ5g-0000000HI7V-3hK5 for linux-arm-kernel@lists.infradead.org; Thu, 28 Aug 2025 00:02:09 +0000 Received: by mail-pf1-x44a.google.com with SMTP id d2e1a72fcca58-770593ba14fso519150b3a.2 for ; Wed, 27 Aug 2025 17:02:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1756339327; x=1756944127; darn=lists.infradead.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=vhbQgqknyAyVeKaXs8kP6grJ1hrwQUkSmJiE25IRpuQ=; b=aLQsNc5VcQyFphTAsJy6ijoKrLolbsComEwb/wy+j+TUUH2UCLbtxQvVHijA+X9Xp+ PVVKwxorK4sjsqC5dwPx9EH/L6b686s67yzk9H/CRmjJ4sqDWIIEGquWxO+16UKD4EEo TKU9sD54SAAn6Zw+dggPgGD5l/zEzZmljzpkTytFYsitAG4NzKtJgzv5zsmV8rlew97t eSvqhJsxhBQAOQqWrivKQryeIIiyyZl1Neo8eRPSuG2M5XFvmoBMc/2wku287FbHfx6V IMpASm5fUWgpDUDRtngZkcKQErVDjKov2LbHrMBXV7lbjUT0h5H4tgNGusTW9M4XSbYm pFHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756339327; x=1756944127; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=vhbQgqknyAyVeKaXs8kP6grJ1hrwQUkSmJiE25IRpuQ=; b=VbeZdsLURaZivUwD21JiU47PsUr9GXPO9kXRb0x95xj0yPuizmF86sieeV/5wVm77X PagJW7kgfDcSlwd+0FCKo6yGbgvMvtHWNDjLfzrbAetSuUH03uGx9qCeUAVwiIxvCShg SuWauT6iIgsC25Y1g0IbwFdjuDLsCC4dZW7Ba/DYA+g0SagqHjsGL8zCxc3HyTBAstwb OwfvKNzcO/aZyeWTBjvvZsEyh5a+0qhtdcIC/cbZuKPuy0TJWwbOYELNIk7DcqSLpdpM gm7pXKoYdO8UNWwflZGjn+p3rcymunEJow+uU8Rovbb3Mo+I7poxGOD5x0PRoCQhzSal L12A== X-Forwarded-Encrypted: i=1; AJvYcCV113FSeSSsxxnXwPNh88RNcqIu+aNwzm2WrUGl0eNl/GksvCz/IfNXIBLnmIm++xj4gCGvNc2mAh2RY8PzBKbw@lists.infradead.org X-Gm-Message-State: AOJu0Yzr1EjA06d2sBxipkbp/5qlGQ54sPAHp9uT5TZLSdC4s1tmlP/m guG6CEP/L/O/aXdqwELHfJB/Oo7XoVbdYJZIgzDqYbjChqB6zZvsqUQLDMCGy3B3wYxH4Gnhr7b eEplbTw== X-Google-Smtp-Source: AGHT+IFSTSPK462uYm9CJ0EAHOKjQ8TiWstiYBGpgePwdPA6VvAffLDDZpu/ZHt6d1MsFofssMNf6pVc4TI= X-Received: from pfbdr10.prod.google.com ([2002:a05:6a00:4a8a:b0:772:a5a:298b]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:4b46:b0:76e:885a:c1c9 with SMTP id d2e1a72fcca58-7702fc24f39mr26347774b3a.27.1756339327187; Wed, 27 Aug 2025 17:02:07 -0700 (PDT) Date: Wed, 27 Aug 2025 17:01:52 -0700 In-Reply-To: <20250828000156.23389-1-seanjc@google.com> Mime-Version: 1.0 References: <20250828000156.23389-1-seanjc@google.com> X-Mailer: git-send-email 2.51.0.268.g9569e192d0-goog Message-ID: <20250828000156.23389-4-seanjc@google.com> Subject: [PATCH v2 3/7] Drivers: hv: Disable IRQs only after handling pending work before VTL return From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Catalin Marinas , Will Deacon , Tianrui Zhao , Bibo Mao , Huacai Chen , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Peter Zijlstra , Andy Lutomirski , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki Cc: 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="UTF-8" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250827_170208_921892_FFE37A51 X-CRM114-Status: GOOD ( 13.07 ) 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: , Reply-To: Sean Christopherson Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Swap the order of checking for TIF-based work and cancellation, and disable IRQs only after checking and processing TIF-based work; checking TIF with IRQs enabled is a-ok, e.g. IRQs and preemption _must_ be enabled before handling the pending work. Signed-off-by: Sean Christopherson --- drivers/hv/mshv_vtl_main.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/hv/mshv_vtl_main.c b/drivers/hv/mshv_vtl_main.c index aa09a76f0eff..4ca13c54c0a0 100644 --- a/drivers/hv/mshv_vtl_main.c +++ b/drivers/hv/mshv_vtl_main.c @@ -735,16 +735,8 @@ static int mshv_vtl_ioctl_return_to_lower_vtl(void) struct hv_vp_assist_page *hvp; int ret; - local_irq_save(irq_flags); - if (READ_ONCE(mshv_vtl_this_run()->cancel)) { - local_irq_restore(irq_flags); - preempt_enable(); - return -EINTR; - } - ti_work = READ_ONCE(current_thread_info()->flags); if (unlikely(ti_work & VTL0_WORK)) { - local_irq_restore(irq_flags); preempt_enable(); ret = mshv_do_pre_guest_mode_work(ti_work); if (ret) @@ -753,6 +745,13 @@ static int mshv_vtl_ioctl_return_to_lower_vtl(void) continue; } + local_irq_save(irq_flags); + if (READ_ONCE(mshv_vtl_this_run()->cancel)) { + local_irq_restore(irq_flags); + preempt_enable(); + return -EINTR; + } + mshv_vtl_return(&mshv_vtl_this_run()->cpu_context); local_irq_restore(irq_flags); -- 2.51.0.268.g9569e192d0-goog