From nobody Sat Feb 7 18:21:23 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 791EA2BB13 for ; Wed, 3 Jul 2024 21:12:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720041157; cv=none; b=KboIhX8mzgYvZjpnQSrNRfE9oxI4y8AcfixHsVhIEEZH6NxQ1FEBb1fO9VrK8cGnfT/K+vKpapCxprZaBLLkAAHqvUUgYncEPk5v0UgdeDHU8e0IssS8EZbsOSKXHjll0OxXbgcb1WmjLP0he9zEkXm8bF8n4U72w4I57GhHDaU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720041157; c=relaxed/simple; bh=yd6M+ZDcYM9C11Y36IJGtzA/KIGidYoe/KhiIb0ULjE=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=pdQjeWuaMJh5qcgpsoaHk0EDGMEySbNpnv6pxzTIRrkFletm7r81tGBBQSadGNECHrdGKubLLAf4foDPCsEuFPwr1rKyl8YOg4GYoXobrOX1ryfWkk+S9jOJrrhHBpIv3gD4bqDXOsTciXZLWrt31QFWfsb08Mc7lxs3WDcfMpg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 574C9C2BD10; Wed, 3 Jul 2024 21:12:36 +0000 (UTC) Date: Wed, 3 Jul 2024 17:12:35 -0400 From: Steven Rostedt To: Linus Torvalds Cc: LKML , Masami Hiramatsu , Mathieu Desnoyers Subject: [GIT PULL] tracing: Fix ioctl conflict with memmapped ring buffer ioctl Message-ID: <20240703171235.68d02755@rorschach.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Linus, tracing: Fix ioctl conflict with memmapped ring buffer ioctl It was reported that the ioctl() number used to update the ring buffer memory mapping conflicted with the TCGETS ioctl causing strace to report: $ strace -e ioctl stty ioctl(0, TCGETS or TRACE_MMAP_IOCTL_GET_READER, {c_iflag=3DICRNL|IXON, c_= oflag=3DNL0|CR0|TAB0|BS0|VT0|FF0|OPOST|ONLCR, c_cflag=3DB38400|CS8|CREAD, c= _lflag=3DISIG|ICANON|ECHO|ECHOE|ECHOK|IEXTEN|ECHOCTL|ECHOKE, ...}) =3D 0 Since this ioctl hasn't been in a full release yet, change it from "T", 0x1 to "R" 0x20, and also reserve 0x20-0x2F for future ioctl commands, as some more are being worked on for the future. Please pull the latest trace-v6.10-rc6 tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git trace-v6.10-rc6 Tag SHA1: 944abfe5775e0d509546ed6b586d8c32df37c263 Head SHA1: 4ecaf7e98a3ae0c843d67c76649ecc694232834b Steven Rostedt (Google) (1): tracing: Have memmapped ring buffer use ioctl of "R" range 0x20-2F ---- Documentation/userspace-api/ioctl/ioctl-number.rst | 1 + include/uapi/linux/trace_mmap.h | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) --------------------------- commit 4ecaf7e98a3ae0c843d67c76649ecc694232834b Author: Steven Rostedt (Google) Date: Tue Jul 2 15:33:54 2024 -0400 tracing: Have memmapped ring buffer use ioctl of "R" range 0x20-2F =20 To prevent conflicts with other ioctl numbers to allow strace to have an idea of what is happening, add the range of ioctls for the trace buffer mapping from _IO("T", 0x1) to the range of "R" 0x20 - 0x2F. =20 Link: https://lore.kernel.org/linux-trace-kernel/20240630105322.GA17573= @altlinux.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240630213626.GA23566= @altlinux.org/ =20 Cc: Jonathan Corbet Fixes: cf9f0f7c4c5bb ("tracing: Allow user-space mapping of the ring-bu= ffer") Link: https://lore.kernel.org/20240702153354.367861db@rorschach.local.h= ome Reported-by: "Dmitry V. Levin" Reviewed-by: Mathieu Desnoyers Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documenta= tion/userspace-api/ioctl/ioctl-number.rst index a141e8e65c5d..9a97030c6c8d 100644 --- a/Documentation/userspace-api/ioctl/ioctl-number.rst +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst @@ -186,6 +186,7 @@ Code Seq# Include File = Comments 'Q' all linux/soundcard.h 'R' 00-1F linux/random.h confl= ict! 'R' 01 linux/rfkill.h confl= ict! +'R' 20-2F linux/trace_mmap.h 'R' C0-DF net/bluetooth/rfcomm.h 'R' E0 uapi/linux/fsl_mc.h 'S' all linux/cdrom.h confl= ict! diff --git a/include/uapi/linux/trace_mmap.h b/include/uapi/linux/trace_mma= p.h index bd1066754220..c102ef35d11e 100644 --- a/include/uapi/linux/trace_mmap.h +++ b/include/uapi/linux/trace_mmap.h @@ -43,6 +43,6 @@ struct trace_buffer_meta { __u64 Reserved2; }; =20 -#define TRACE_MMAP_IOCTL_GET_READER _IO('T', 0x1) +#define TRACE_MMAP_IOCTL_GET_READER _IO('R', 0x20) =20 #endif /* _TRACE_MMAP_H_ */