From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793630961; b=gaWWnMty+VK+tGOFcXu7kBLyVRkmxTJLwfuwLwEnj92wmYao8lBrk5xEkFrNSa4eJ6bb ZvBMUp0Wb5gFs730JhnVhv92NVx02fQSPGwCW4ht+UPmp/vodKs48E2sixeaH0GCCw3/r iHNnW1g8OtYgQJYjE5tehThd3vxQgwOOq2+hSZ8taWyoOHEnuX+8YaU/1pI6onp6BvTCc UWb2LiRU4+K0b0QASququK8OTvQw4cEzEAGKUP+Vd2MMKEX9kwgeVxbbTHHhPWZq7zrbR q8qZBADWvl8CK0/4jS8qya2Z/J/2f/wuBvZ7dpLdvcavYEQDAvzBZcGPrdThQqIpXTQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793630961; h=Received:DKIM-Signature:From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:References:In-Reply-To:To:Cc: X-Mailer; bh=jrxxeu9FMCeaH9PPG0vvIdaQylBKAxxjB5EHgDoyGNY=; b=PQGZTmiCRS1da8d4qYvuaWD23R52KxSOuA3WK05gRV70ChA9t/qk1Red8R3F8AGe4zTt irMRMczkIaDKrQ/LYnynBt58Qwo1M43jnyNEJL4M90A8KnsWvXdG99w2/b/RLoMYwINuA uf2wT7JEBLWa4BnDExKx1Vrmjdx/O/JrxFcyXyxHfuS2x+XF9TB2x724uudWKsZYquBtc tB/x/PIHIdQtHpOKEBZ8pXDTU5udO64NRnl35HJP1ulyGcTjaiqKJvmsD5Ploq+bmkmus dxbcmlt9DX5vSFd6LOxUy7uEPA4qp761uoOTeIqf5Hv26CU11z9e6wo3bo5eAWmltsg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ByuxxP2Y; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5EF2F606ABBD; Mon, 2 Nov 2026 14:49:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ByuxxP2Y Received: by smtp.kernel.org (Postfix) with ESMTPSA id D423F1F00A16; Mon, 2 Nov 2026 14:49:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793630961; bh=jrxxeu9FMCeaH9PPG0vvIdaQylBKAxxjB5EHgDoyGNY=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=ByuxxP2Y0aL4EQ4HwE1D5VE6bk9SBZU78IecQNaoL/QqN2Y6I7ABFAIAs9mVScHNH SgYUHz+A/rbabkW8D5dGgo432jVpFe7FT/P6H+jA3wauUd5cjNIX0RjXLHQxPeZnwc ZHYHReIZ20MHWB1oFcj0/0Oig7/cat0HqyX7ecJpsbua1wSW9hsT6O0sgpvSBLGhfY xPgK550INOHZoI47HH3iTcy4uMo2SA7+Bla5KpVWGtw3gSqFOEGcd2cLWE8Js/8MoA b91eSZEjTRDcbicVa76y8vSAq+2z0cdK8bBOdtnHVxMyTugmPIsG5XGIzFlkoOVhvM mmiHRSg+JBAAQ== From: Christian Brauner Date: Mon, 02 Nov 2026 15:48:41 +0100 Subject: [PATCH RFC 01/16] proc: drop the compat file operations X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261102-work-procfs-core-v1-1-75df35e4f8b8@kernel.org> References: <20261102-work-procfs-core-v1-0-75df35e4f8b8@kernel.org> In-Reply-To: <20261102-work-procfs-core-v1-0-75df35e4f8b8@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jann Horn , Josef Bacik , Chris Mason , Jeff Layton , NeilBrown , Eric Dumazet , Thomas Gleixner , Al Viro , Jonathan Corbet , Christoph Hellwig , Greg Kroah-Hartman , Joel Granados , Kees Cook , Jan Kara , Jan Kara , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-um@lists.infradead.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, platform-driver-x86@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-sound@vger.kernel.org, netfilter-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, ibm-acpi-devel@lists.sourceforge.net, jfs-discussion@lists.sourceforge.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cifs@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, sparclinux@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-doc@vger.kernel.org, linux-serial@vger.kernel.org, linux-atm-general@lists.sourceforge.net, Takashi Iwai , linux-input@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, linux-modules@vger.kernel.org, linux-debuggers@vger.kernel.org, "Christian Brauner (Amutable)" , Chuck Lever X-Mailer: b4 0.17-dev procfs has both sets of file operations twice, with and without ->compat_ioctl(), and picks the one with it for entries that have ->proc_compat_ioctl(). That's from commit 778f3dd5a13c ("Fix procfs compat_ioctl regression") when a file without ->compat_ioctl() went through the translation tables in fs/compat_ioctl.c and one with it didn't. Those tables are gone since commit 77b9040195de ("compat_ioctl: simplify the implementation"). compat_sys_ioctl() answers -ENOTTY for a file without ->compat_ioctl() now, which is what proc_reg_compat_ioctl() answers for an entry without ->proc_compat_ioctl(). So always set ->compat_ioctl() and drop the second set of file operations and the flag that picked it. No functional changes. Signed-off-by: Christian Brauner (Amutable) --- fs/proc/generic.c | 4 ---- fs/proc/inode.c | 45 +++------------------------------------------ fs/proc/internal.h | 9 --------- include/linux/proc_fs.h | 1 - 4 files changed, 3 insertions(+), 56 deletions(-) diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 23fc026d7bbb..761f9958558f 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -445,10 +445,6 @@ static void pde_set_flags(struct proc_dir_entry *pde) pde->flags |= PROC_ENTRY_PERMANENT; if (proc_ops->proc_read_iter) pde->flags |= PROC_ENTRY_proc_read_iter; -#ifdef CONFIG_COMPAT - if (proc_ops->proc_compat_ioctl) - pde->flags |= PROC_ENTRY_proc_compat_ioctl; -#endif if (proc_ops->proc_lseek) pde->flags |= PROC_ENTRY_proc_lseek; } diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 2d65f3c8ec03..18f6490bfe77 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -410,6 +410,8 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned } return rv; } +#else +#define proc_reg_compat_ioctl NULL #endif static int pde_mmap(struct proc_dir_entry *pde, struct file *file, struct vm_area_struct *vma) @@ -569,6 +571,7 @@ static const struct file_operations proc_reg_file_ops = { .write = proc_reg_write, .poll = proc_reg_poll, .unlocked_ioctl = proc_reg_unlocked_ioctl, + .compat_ioctl = proc_reg_compat_ioctl, .mmap = proc_reg_mmap, .get_unmapped_area = proc_reg_get_unmapped_area, #ifndef CONFIG_MMU @@ -585,39 +588,6 @@ static const struct file_operations proc_iter_file_ops = { .splice_read = copy_splice_read, .poll = proc_reg_poll, .unlocked_ioctl = proc_reg_unlocked_ioctl, - .mmap = proc_reg_mmap, - .get_unmapped_area = proc_reg_get_unmapped_area, -#ifndef CONFIG_MMU - .mmap_capabilities = proc_reg_mmap_capabilities, -#endif - .open = proc_reg_open, - .release = proc_reg_release, -}; - -#ifdef CONFIG_COMPAT -static const struct file_operations proc_reg_file_ops_compat = { - .llseek = proc_reg_llseek, - .read = proc_reg_read, - .write = proc_reg_write, - .poll = proc_reg_poll, - .unlocked_ioctl = proc_reg_unlocked_ioctl, - .compat_ioctl = proc_reg_compat_ioctl, - .mmap = proc_reg_mmap, - .get_unmapped_area = proc_reg_get_unmapped_area, -#ifndef CONFIG_MMU - .mmap_capabilities = proc_reg_mmap_capabilities, -#endif - .open = proc_reg_open, - .release = proc_reg_release, -}; - -static const struct file_operations proc_iter_file_ops_compat = { - .llseek = proc_reg_llseek, - .read_iter = proc_reg_read_iter, - .splice_read = copy_splice_read, - .write = proc_reg_write, - .poll = proc_reg_poll, - .unlocked_ioctl = proc_reg_unlocked_ioctl, .compat_ioctl = proc_reg_compat_ioctl, .mmap = proc_reg_mmap, .get_unmapped_area = proc_reg_get_unmapped_area, @@ -627,7 +597,6 @@ static const struct file_operations proc_iter_file_ops_compat = { .open = proc_reg_open, .release = proc_reg_release, }; -#endif static const char *proc_get_link(struct dentry *dentry, struct inode *inode, @@ -683,14 +652,6 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de) inode->i_fop = &proc_iter_file_ops; else inode->i_fop = &proc_reg_file_ops; -#ifdef CONFIG_COMPAT - if (pde_has_proc_compat_ioctl(de)) { - if (pde_has_proc_read_iter(de)) - inode->i_fop = &proc_iter_file_ops_compat; - else - inode->i_fop = &proc_reg_file_ops_compat; - } -#endif } else if (S_ISDIR(inode->i_mode)) { inode->i_op = de->proc_iops; inode->i_fop = de->proc_dir_ops; diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 04f7ce2b24ed..268a0523be12 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -92,15 +92,6 @@ static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde) return pde->flags & PROC_ENTRY_proc_read_iter; } -static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde) -{ -#ifdef CONFIG_COMPAT - return pde->flags & PROC_ENTRY_proc_compat_ioctl; -#else - return false; -#endif -} - static inline bool pde_has_proc_lseek(const struct proc_dir_entry *pde) { return pde->flags & PROC_ENTRY_proc_lseek; diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 47d7deaeed8f..6ad5150020bf 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -26,7 +26,6 @@ enum { #endif PROC_ENTRY_proc_read_iter = 1U << 1, - PROC_ENTRY_proc_compat_ioctl = 1U << 2, PROC_ENTRY_proc_lseek = 1U << 3, PROC_ENTRY_FORCE_LOOKUP = 1U << 7, -- 2.53.0