All of lore.kernel.org
 help / color / mirror / Atom feed
From: Oleg Nesterov <oleg@redhat.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Thomas Gleixner <tglx@linutronix.de>,
	David Miller <davem@davemloft.net>,
	"Theodore Ts'o" <tytso@mit.edu>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	the arch/x86 maintainers <x86@kernel.org>,
	Network Development <netdev@vger.kernel.org>,
	"linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>,
	Fr??d??ric Weisbecker <fweisbec@gmail.com>
Subject: [PATCH v2] x86: make DR*_RESERVED unsigned long
Date: Fri, 26 Apr 2013 18:38:02 +0200	[thread overview]
Message-ID: <20130426163802.GA30351@redhat.com> (raw)
In-Reply-To: <20130425144818.GA25921@redhat.com>

DR6_RESERVED and DR_CONTROL_RESERVED are used to clear the set
bits in the "unsigned long" data, make them long to ensure that
"&~" doesn't clear the upper bits.

This is only cleanup, the usage of ~DR*_RESERVED is safe but
doesn't look clean and the pattern is error prone.

	- do_debug:

		dr6 &= ~DR6_RESERVED;

	  this also wrongly clears 32-63 bits. Fortunately these
	  bits are reserved and must be zero.

	- ptrace_write_dr7:

		data &= ~DR_CONTROL_RESERVED;

	  on __i386__ this mixes long/int but sizeof should be the
	  same.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
 arch/x86/include/uapi/asm/debugreg.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/uapi/asm/debugreg.h b/arch/x86/include/uapi/asm/debugreg.h
index 3c0874d..c0c1b89 100644
--- a/arch/x86/include/uapi/asm/debugreg.h
+++ b/arch/x86/include/uapi/asm/debugreg.h
@@ -15,7 +15,7 @@
    are either reserved or not of interest to us. */
 
 /* Define reserved bits in DR6 which are always set to 1 */
-#define DR6_RESERVED	(0xFFFF0FF0)
+#define DR6_RESERVED	(0xFFFF0FF0UL)
 
 #define DR_TRAP0	(0x1)		/* db0 */
 #define DR_TRAP1	(0x2)		/* db1 */
@@ -65,7 +65,7 @@
    gdt or the ldt if we want to.  I am not sure why this is an advantage */
 
 #ifdef __i386__
-#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */
+#define DR_CONTROL_RESERVED (0xFC00UL) /* Reserved by Intel */
 #else
 #define DR_CONTROL_RESERVED (0xFFFFFFFF0000FC00UL) /* Reserved */
 #endif
-- 
1.5.5.1

  reply	other threads:[~2013-04-26 16:38 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CA+55aFwpLu0qNms=hkQr43yqD0K9DgESNm91OEWKT1ZuT8MU6Q@mail.gmail.com>
2013-04-23  0:23 ` Unsigned widening casts of binary "not" operations Linus Torvalds
2013-04-23  8:59   ` David Laight
2013-04-23  8:59     ` David Laight
2013-04-23 14:29     ` Linus Torvalds
2013-04-23 15:24       ` David Laight
2013-04-23 15:24         ` David Laight
2013-04-23 15:42         ` Linus Torvalds
2013-04-23 15:52           ` Theodore Ts'o
2013-04-23 16:05             ` Linus Torvalds
2013-04-23 17:37           ` David Miller
2013-04-23 17:52             ` Linus Torvalds
2013-04-23 17:56               ` David Miller
2013-04-23 18:21                 ` Linus Torvalds
2013-04-24 12:36             ` Geert Uytterhoeven
2013-04-23  0:32 ` H. Peter Anvin
2013-04-23 13:00 ` Theodore Ts'o
2013-04-24  7:26 ` Ingo Molnar
2013-04-24  7:47   ` Cyrill Gorcunov
2013-04-25  1:13     ` Lin Ming
2013-04-24 17:07   ` [PATCH] x86: make DR*_RESERVED unsigned long Oleg Nesterov
2013-04-24 18:45     ` H. Peter Anvin
2013-04-25 14:48       ` Oleg Nesterov
2013-04-26 16:38         ` Oleg Nesterov [this message]
2013-04-26 16:44           ` [PATCH v2] " H. Peter Anvin
2013-04-26 17:15             ` Oleg Nesterov
2013-04-27 14:45               ` Oleg Nesterov
2013-04-27 16:20                 ` H. Peter Anvin
2013-04-28  0:58                 ` Frederic Weisbecker
2013-04-28 17:27                   ` Oleg Nesterov
2013-04-28 17:32                     ` H. Peter Anvin
2013-04-28 17:39                       ` Oleg Nesterov
2013-04-28 17:43                         ` H. Peter Anvin
2013-04-24 22:48     ` [PATCH] " Frederic Weisbecker
2013-04-24 23:06       ` H. Peter Anvin
2013-04-24 23:31         ` Frederic Weisbecker
2013-04-25  1:20           ` H. Peter Anvin
2013-04-26 14:20   ` [tip:perf/core] perf/x86/intel/P4: Robistify P4 PMU types tip-bot for Ingo Molnar
2013-04-26 16:13     ` Borislav Petkov
2013-04-26 16:24       ` Cyrill Gorcunov
2013-04-26 16:39         ` Borislav Petkov
2013-04-26 16:46           ` Cyrill Gorcunov
2013-04-27 16:14             ` Borislav Petkov
2013-04-27 16:33               ` Cyrill Gorcunov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20130426163802.GA30351@redhat.com \
    --to=oleg@redhat.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=davem@davemloft.net \
    --cc=fweisbec@gmail.com \
    --cc=gorcunov@gmail.com \
    --cc=hpa@zytor.com \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --cc=tytso@mit.edu \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.