From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 C8FA52F659C for ; Tue, 6 Jan 2026 17:34:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767720888; cv=none; b=GG7QuO4vmXFhZoigpWwJzBk0SPB1ZE4i2qZJJkF9IKIkoztGyiU+BOQQ8Si1pFttN9HhGFTSAt3RV2sbCuxPVhs4WQDe4lxRuH5NC/s/95c6+rgm1mtB9XhlHfiZosRjiDlXtc1YVa8sSX5lzXkO9a4vSZJsx2novObbxIcI3XU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767720888; c=relaxed/simple; bh=oG+5BObDcTDi1x+Km41qa3lPinM+Zu9ZcLwgxUaBtls=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=SQJA5xMbFF1OHn0sQ8+z46WmbQ1TPXZAsUhFwPeK/GZwJGU+kqSBZUsV5XyQhW138D8/M6wc+M29aC6xIdyS7R9zS8lGL5R5xrm45SBUH8LXNlafOelPMRhSanNbILAHwEDyCShksZPchOVM52iJkGoyTqspktDCQ+BIPTW4N+Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=vFA67m4L; arc=none smtp.client-ip=209.85.214.202 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=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="vFA67m4L" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-29f26fc6476so20506795ad.1 for ; Tue, 06 Jan 2026 09:34:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1767720886; x=1768325686; darn=vger.kernel.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=3u/SRXiaOkDG6uvCHXyBdLmp6hdaJa1OYUaHTRQhklQ=; b=vFA67m4L7AOOx9/+TL/Jx2QVjjGTI66vHJr6gjO6y16zX39ySg71db+hHqLjvAWOro CuEOTCX5eQXkoDxDJH7bYKr67C+eVYyMI4T5pA1GEwPe6G/fAFbDv6YEMparCYiroSis FzeV/6/QMRxQgx495+2NfP+DJZuU8cGkVoVolDEGylg8uIl1qvOFr8XibFR+DMGrB3u/ C1dqyMmH0bHFwveF0obNkRkv8py2Xd/SuaJSgYOzR1ugJIpv4stucrdG8NKAT6x8U8KQ Z0hcJ06/x+oROCkgGzzxmYcjDAIAM1zUqCu20MpHaJ+TQZZG7C7n7DuxcHRPsNAQrQRY LVQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767720886; x=1768325686; 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=3u/SRXiaOkDG6uvCHXyBdLmp6hdaJa1OYUaHTRQhklQ=; b=H8iEOuOOO4UdDwC8AWUk3KpIdlWZ4dJ+/b3jM6pyFnPdvC4FPvIVvR60ajCSk3bZY0 0oV1fWlk0/1IGnOC0uLcAmcLzEqpH/Dx3zAMMdC7zuD9lVslyPrbVFeDw08jR6slSXso EmInl8VOhgR1XA7AM/Zp0QabSKXPAYkegCscmiYT9tKOkjx+zzCyY3A2+SW0bUqzHcTF 3kkHMAzIVEOdldn10Uguxb8ZGs5g7vYMbrn1CGx4yAZCaqM2NldYDihhyJ7Tnez41G3p iUoZr2EWia94mpHiHPpLQhR6orTFF+1bgvr8VTsSUiGAbCxQMmtgpU7zmcw9KlnxuV17 UCnQ== X-Forwarded-Encrypted: i=1; AJvYcCXymSWiiRY9v3W3j1PTbaVoUQPf1A3vkFsF2O5S9WCRc/gx0oXKOKSegx91EY0IV8hHh40erq7jl2eKH5k=@vger.kernel.org X-Gm-Message-State: AOJu0Yy5dH+ykhWESuqNmenY6CzdUKyi8zZJ0fU4Sv+/zacY5Vi5+TJy PLzz8nYUWAUc7jf80ompGpwImbsuWDlWFNiNA63df9Jb+WqW8M/+YYwscJ5+GkwHLeDMKvZ5zow OXACyWw== X-Google-Smtp-Source: AGHT+IEPNTpv7HvlOHxKD/0Uliz6EXEzXccXZp3/d4Ho/3M791oWBuctzoLTQdPVExufzvSsYW/MQKp+4uQ= X-Received: from pjbqb12.prod.google.com ([2002:a17:90b:280c:b0:34a:4aa7:b774]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:58d0:b0:340:fb6a:cb4c with SMTP id 98e67ed59e1d1-34f5f2fb2camr2910890a91.30.1767720886019; Tue, 06 Jan 2026 09:34:46 -0800 (PST) Date: Tue, 6 Jan 2026 09:34:44 -0800 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260104093221.494510-1-alessandro@0x65c.net> Message-ID: Subject: Re: [PATCH] KVM: x86: Retry guest entry on -EBUSY from kvm_check_nested_events() From: Sean Christopherson To: Alessandro Ratti Cc: pbonzini@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+1522459a74d26b0ac33a@syzkaller.appspotmail.com Content-Type: text/plain; charset="us-ascii" On Tue, Jan 06, 2026, Sean Christopherson wrote: > On Sun, Jan 04, 2026, Alessandro Ratti wrote: > I'll post the below as part of a series, as there is at least one cleanup that > can be done on top to consolidate handling of EBUSY, Gah, I was wrong. I was thinking that morphing EBUSY to '0' could be moved into a common helper, but kvm_apic_accept_events() needs to bail immediately on EBUSY, i.e. needs to see EBUSY, not '0'. I'll post this as a standalone patch and then try to add WARNs in a separate series. > and I'm hopeful that the spirit of the WARN can be preserved, e.g. by > adding/extending WARNs in paths where KVM (re)injects events.