From: Christoph Hellwig <hch@infradead.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>,
Russell King <linux@armlinux.org.uk>,
Alexander Viro <viro@zeniv.linux.org.uk>,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org,
linux-mm@kvack.org
Subject: Re: [PATCH v2 2/9] ARM: traps: use get_kernel_nofault instead of set_fs()
Date: Sat, 19 Sep 2020 06:27:46 +0100 [thread overview]
Message-ID: <20200919052746.GG30063@infradead.org> (raw)
In-Reply-To: <20200918124624.1469673-3-arnd@arndb.de>
On Fri, Sep 18, 2020 at 02:46:17PM +0200, Arnd Bergmann wrote:
> ARM uses set_fs() and __get_user() to allow the stack dumping code to
> access possibly invalid pointers carefully. These can be changed to the
> simpler get_kernel_nofault(), and allow the eventual removal of set_fs().
>
> dump_instr() will print either kernel or user space pointers,
> depending on how it was called. For dump_mem(), I assume we are only
> interested in kernel pointers, and the only time that this is called
> with user_mode(regs)==true is when the regs themselves are unreliable
> as a result of the condition that caused the trap.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@infradead.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
Russell King <linux@armlinux.org.uk>,
Christoph Hellwig <hch@infradead.org>,
linux-mm@kvack.org, Alexander Viro <viro@zeniv.linux.org.uk>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 2/9] ARM: traps: use get_kernel_nofault instead of set_fs()
Date: Sat, 19 Sep 2020 06:27:46 +0100 [thread overview]
Message-ID: <20200919052746.GG30063@infradead.org> (raw)
In-Reply-To: <20200918124624.1469673-3-arnd@arndb.de>
On Fri, Sep 18, 2020 at 02:46:17PM +0200, Arnd Bergmann wrote:
> ARM uses set_fs() and __get_user() to allow the stack dumping code to
> access possibly invalid pointers carefully. These can be changed to the
> simpler get_kernel_nofault(), and allow the eventual removal of set_fs().
>
> dump_instr() will print either kernel or user space pointers,
> depending on how it was called. For dump_mem(), I assume we are only
> interested in kernel pointers, and the only time that this is called
> with user_mode(regs)==true is when the regs themselves are unreliable
> as a result of the condition that caused the trap.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
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next prev parent reply other threads:[~2020-09-19 5:27 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-18 12:46 [PATCH v2 0/9] ARM: remove set_fs callers and implementation Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 1/9] mm/maccess: fix unaligned copy_{from,to}_kernel_nofault Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 1/9] mm/maccess: fix unaligned copy_{from, to}_kernel_nofault Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 2/9] ARM: traps: use get_kernel_nofault instead of set_fs() Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-19 5:27 ` Christoph Hellwig [this message]
2020-09-19 5:27 ` Christoph Hellwig
2020-09-18 12:46 ` [PATCH v2 3/9] ARM: oabi-compat: add epoll_pwait handler Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-21 12:54 ` Sasha Levin
2020-09-21 13:27 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 4/9] ARM: syscall: always store thread_info->syscall Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 5/9] ARM: oabi-compat: rework epoll_wait/epoll_pwait emulation Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-19 5:32 ` Christoph Hellwig
2020-09-19 5:32 ` Christoph Hellwig
2020-09-26 18:30 ` Arnd Bergmann
2020-09-26 18:30 ` Arnd Bergmann
2020-09-26 18:30 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 6/9] ARM: oabi-compat: rework sys_semtimedop emulation Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 7/9] ARM: oabi-compat: rework fcntl64() emulation Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 8/9] ARM: uaccess: add __{get,put}_kernel_nofault Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-18 12:46 ` [PATCH v2 9/9] ARM: uaccess: remove set_fs() implementation Arnd Bergmann
2020-09-18 12:46 ` Arnd Bergmann
2020-09-19 5:27 ` [PATCH v2 0/9] ARM: remove set_fs callers and implementation Christoph Hellwig
2020-09-19 5:27 ` Christoph Hellwig
2020-09-25 13:40 ` Arnd Bergmann
2020-09-25 13:40 ` Arnd Bergmann
2020-09-25 13:40 ` Arnd Bergmann
2020-09-26 6:49 ` Christoph Hellwig
2020-09-26 6:49 ` Christoph Hellwig
2021-07-05 6:01 ` Christoph Hellwig
2021-07-05 6:01 ` Christoph Hellwig
2021-07-22 17:27 ` Arnd Bergmann
2021-07-22 17:27 ` Arnd Bergmann
2021-07-22 17:27 ` Arnd Bergmann
2020-09-19 8:19 ` Russell King - ARM Linux admin
2020-09-19 8:19 ` Russell King - ARM Linux admin
2020-09-25 14:08 ` Arnd Bergmann
2020-09-25 14:08 ` Arnd Bergmann
2020-09-25 14:08 ` Arnd Bergmann
2020-09-25 15:30 ` Arnd Bergmann
2020-09-25 15:30 ` Arnd Bergmann
2020-09-25 15:30 ` Arnd Bergmann
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