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AJvYcCWnsK/aCKq/rWwJJuakOw6G+wT08UAVvZ6C1+GI1QCeB8QnuVLfpWa6ApjsS3L7OMFUwABdGeaWqeXFYlu8FAfe1Jv3DbFbt0CRYx6d X-Gm-Message-State: AOJu0YxgXlblZWheiSpUk8vGXeu/hlyxipayU9HSs/be6y8OWPm67Hqh 0WoQvxsTXpqOG1j/vYSuSMMS+TLAiwyMntUClLa7eGnxdEs2Q8gmw1gjTw+8LtKvqfYjK5Rh+mP WNA== X-Google-Smtp-Source: AGHT+IHZIE1aSJKNameo12IiZOPatLKvd0dlaPUQsUUAhUvJrz645sSwhtTznVjkzZVO3C3zlnmmqxLLb2s= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:90a:6b07:b0:2c2:4117:2401 with SMTP id 98e67ed59e1d1-2c27cc5925cmr42158a91.2.1717544282231; Tue, 04 Jun 2024 16:38:02 -0700 (PDT) Date: Tue, 4 Jun 2024 16:29:31 -0700 In-Reply-To: <20240423191649.2885257-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240423191649.2885257-1-seanjc@google.com> X-Mailer: git-send-email 2.45.1.288.g0e0cd299f1-goog Message-ID: <171754322115.2778750.1004415588461260295.b4-ty@google.com> Subject: Re: [PATCH] Revert "KVM: async_pf: avoid recursive flushing of work items" From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Xu Yilun Content-Type: text/plain; charset="utf-8" On Tue, 23 Apr 2024 12:16:49 -0700, Sean Christopherson wrote: > Now that KVM does NOT gift async #PF workers a "struct kvm" reference, > don't bother skipping "done" workers when flushing/canceling queued > workers, as the deadlock that was being fudged around can no longer occur. > When workers, i.e. async_pf_execute(), were gifted a referenced, it was > possible for a worker to put the last reference and trigger VM destruction, > i.e. trigger flushing of a workqueue from a worker in said workqueue. > > [...] Applied to kvm-x86 generic, thanks! [1/1] Revert "KVM: async_pf: avoid recursive flushing of work items" https://github.com/kvm-x86/linux/commit/778c350eb580 -- https://github.com/kvm-x86/linux/tree/next