From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 32CB04A8A04; Tue, 15 Sep 2026 11:36:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789472200; cv=none; b=Qds8/uclOY7MnZCuSz3IsRFr/3yDbMAYsBFgxnLqQuzu4FvnxDt+Oed94pE4wSdftEaynFasziOj8vBSKGtGNaFE7dM+pFogMa5KoqE8EcYndslGkOzpeGCkYrx/j4mmiQsp5Yym73ytQiZ8UkrOhkW61lMEmKSrCPEG+LxX8y4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789472200; c=relaxed/simple; bh=KLCbLLJNzFhK9KnJoDv8kDUlKXi4pqPjbkN6aCwr8bo=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=humiqd6CmvDgM0K5Pr6eCu60EC7evt2AEdsotXxaca51XmF55QVKeVc51SCIa0V1ORN9N63cf6R+H/pl5CVzSAUkB+q2D+c4HvJxgN6ScaPjV3GA878zDqKt5rGSP7I3wUiLktdbwlesOuLSxI7lNlXrWlt6fwyUjQ5fMV9dOzI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=keM2MELZ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="keM2MELZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 948881F00893; Tue, 15 Sep 2026 11:36:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789472198; bh=dR2AT7slAh5QiQGKBciNLhR24TAk5bJ3ys4Ah5Rt7mE=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=keM2MELZ8tMeEj63s6rILS1a6ikUND0cm/hSBjQN5i9zsMHRwumL2LpgndOJca1Aa 97kIpfNmItf2JE76ybod5HhCCbaR3uSYEM810jrmgilIii5FRWRh1O86tNdM0FYWJl 38f1UHzSPEd+hj/T0Nlt8QEoyRs4wb5r4JVdV9i/rSIOmEYhsfaqAD31KqLx/f0h3O ACHfbLbzGXb+++iV7WaxfM+tTIGP+WsUWGxYSjDxuYEbOqm0MVVuZjc4buiK4jUw7O C9LHTBiZSEultvzvuQBhaDEJQMVPhyftCJPppnofTMl7IPUPEYHfgCv4gmlMrEOmjT oPjncB8aAwY0Q== From: Christian Brauner Date: Tue, 15 Sep 2026 13:31:27 +0200 Subject: [PATCH RFC POC 41/50] KVM: guest_memfd: stop putting the descriptor back on failure Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260915-work-fd-reserve-unify-folded-v1-41-4d5217d6b246@kernel.org> References: <20260915-work-fd-reserve-unify-folded-v1-0-4d5217d6b246@kernel.org> In-Reply-To: <20260915-work-fd-reserve-unify-folded-v1-0-4d5217d6b246@kernel.org> To: Linus Torvalds Cc: Alexander Viro , Jann Horn , Jan Kara , Ingo Molnar , Peter Zijlstra , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Oleg Nesterov , linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, Jens Axboe , io-uring@vger.kernel.org, netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-gpio@vger.kernel.org, linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, bpf@vger.kernel.org, David Airlie , virtualization@lists.linux.dev, kvm@vger.kernel.org, kexec@lists.infradead.org, linux-hyperv@vger.kernel.org, "Christian Brauner (Amutable)" X-Mailer: b4 0.17-dev-db0b7 X-Developer-Signature: v=1; a=openpgp-sha256; l=1418; i=brauner@kernel.org; h=from:subject:message-id; bh=KLCbLLJNzFhK9KnJoDv8kDUlKXi4pqPjbkN6aCwr8bo=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWSt1Kk/tfzHImu/Gp6ZRSssN5fyinw4ruUhZCIkyWFT3 bH7k9a5jlIWBjEuBlkxRRaHdpNwueU8FZuNMjVg5rAygQxh4OIUgIm8sWZk6GKcxbHPfdfrbYrn f0Zr1u290KLF8etT65HPSeyxa5JK9zH8jwg7xHPKv6v/9/8HHp3fHOUXznI3MuD7/nrNS8a/OUU arAA= X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Rely on the fd exit path machinery. Signed-off-by: Christian Brauner (Amutable) --- virt/kvm/guest_memfd.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 625e62e1a031..e0d1cb869342 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -526,17 +526,16 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t size, u64 flags) struct gmem_file *f; struct inode *inode; struct file *file; - int fd, err; + const struct fd_slot *fd; + int err; - fd = get_unused_fd_flags(0); - if (fd < 0) - return fd; + fd = fd_prepare(0); + if (IS_ERR(fd)) + return PTR_ERR(fd); f = kzalloc_obj(*f); - if (!f) { - err = -ENOMEM; - goto err_fd; - } + if (!f) + return -ENOMEM; /* __fput() will take care of fops_put(). */ if (!fops_get(&kvm_gmem_fops)) { @@ -575,8 +574,7 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t size, u64 flags) xa_init(&f->bindings); list_add(&f->entry, &GMEM_I(inode)->gmem_file_list); - fd_install(fd, file); - return fd; + return fd_stage(fd, file); err_inode: iput(inode); @@ -584,8 +582,6 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t size, u64 flags) fops_put(&kvm_gmem_fops); err_gmem: kfree(f); -err_fd: - put_unused_fd(fd); return err; } -- 2.53.0