From: Arnd Bergmann <arnd@arndb.de>
To: monstr@monstr.eu
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, john.williams@petalogix.com
Subject: Re: [PATCH 20/30] microblaze_mmu_v1: uaccess MMU update
Date: Wed, 29 Apr 2009 17:55:37 +0200 [thread overview]
Message-ID: <200904291755.38497.arnd@arndb.de> (raw)
In-Reply-To: <49F875B1.2050502@monstr.eu>
On Wednesday 29 April 2009, Michal Simek wrote:
> For powerpc I found these tree references. Where is the __get_user_bad definition?
> arch/powerpc/include/asm/uaccess.h:216:extern long __get_user_bad(void);
> arch/powerpc/include/asm/uaccess.h:263: (x) = __get_user_bad(); \
> arch/powerpc/include/asm/uaccess.h:269: default: (x) = __get_user_bad(); \
>
As I tried to explain, the whole point is that there is no definition
at all, just a declaration.
Normally, the compiler will discard the 'default:' case of get_user,
so the function is not called. However, if you pass a variable of
a length other than 1, 2, or 4, the compiler will generate a function
call to __get_user_bad in the object file. When you try to link
the kernel afterwards, you will get an error message like
Unknown symbol __get_user_bad" for drivers/foo/bar.o
which tells you that some function in drivers/foo/bar.c calls
get_user with an invalid argument.
Arnd <><
next prev parent reply other threads:[~2009-04-29 15:57 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-27 8:31 Microblaze MMU patches monstr
2009-04-27 8:31 ` [PATCH 01/30] microblaze_mmu_v1: Makefiles monstr
2009-04-27 8:31 ` [PATCH 02/30] microblaze_mmu_v1: Kconfig update monstr
2009-04-27 8:31 ` [PATCH 03/30] microblaze_mmu_v1: Add mmu_defconfig monstr
2009-04-27 8:31 ` [PATCH 04/30] microblaze_mmu_v1: MMU update for startup code monstr
2009-04-27 8:31 ` [PATCH 05/30] microblaze_mmu_v1: Alocate TLB for early console monstr
2009-04-27 8:31 ` [PATCH 06/30] microblaze_mmu_v1: TLB low level code monstr
2009-04-27 8:31 ` [PATCH 07/30] microblaze_mmu_v1: MMU initialization monstr
2009-04-27 8:31 ` [PATCH 08/30] microblaze_mmu_v1: mmu.h update monstr
2009-04-27 8:31 ` [PATCH 09/30] microblaze_mmu_v1: Page fault handling high level - fault.c monstr
2009-04-27 8:31 ` [PATCH 10/30] microblaze_mmu_v1: Context handling - mmu_context.c/h monstr
2009-04-27 8:32 ` [PATCH 11/30] microblaze_mmu_v1: Page table - ioremap - pgtable.c/h, section update monstr
2009-04-27 8:32 ` [PATCH 12/30] microblaze_mmu_v1: io.h MMU update monstr
2009-04-27 8:32 ` [PATCH 13/30] microblaze_mmu_v1: pgalloc.h and page.h monstr
2009-04-27 8:32 ` [PATCH 14/30] microblaze_mmu_v1: Update process creation for MMU monstr
2009-04-27 8:32 ` [PATCH 15/30] microblaze_mmu_v1: Update tlb.h and tlbflush.h monstr
2009-04-27 8:32 ` [PATCH 16/30] microblaze_mmu_v1: MMU asm offset update monstr
2009-04-27 8:32 ` [PATCH 17/30] microblaze_mmu_v1: Add CURRENT_TASK for entry.S monstr
2009-04-27 8:32 ` [PATCH 18/30] microblaze_mmu_v1: entry.S, entry.h monstr
2009-04-27 8:32 ` [PATCH 19/30] microblaze_mmu_v1: Update exception handling - MMU exception monstr
2009-04-27 8:32 ` [PATCH 20/30] microblaze_mmu_v1: uaccess MMU update monstr
2009-04-27 8:32 ` [PATCH 21/30] microblaze_mmu_v1: Add MMU related exceptions handling monstr
2009-04-27 8:32 ` [PATCH 22/30] microblaze_mmu_v1: Update linker script for MMU monstr
2009-04-27 8:32 ` [PATCH 23/30] microblaze_mmu_v1: Enable fork syscall for MMU and add fork as vfork for noMMU monstr
2009-04-27 8:32 ` [PATCH 24/30] microblaze_mmu_v1: Traps MMU update monstr
2009-04-27 8:32 ` [PATCH 25/30] microblaze_mmu_v1: Update signal returning address monstr
2009-04-27 8:32 ` [PATCH 26/30] microblaze_mmu_v1: Update cacheflush.h monstr
2009-04-27 8:32 ` [PATCH 27/30] microblaze_mmu_v1: Update dma.h for MMU monstr
2009-04-27 8:32 ` [PATCH 28/30] microblaze_mmu_v1: Elf update monstr
2009-04-27 8:32 ` [PATCH 29/30] microblaze_mmu_v1: stat.h MMU update monstr
2009-04-27 8:32 ` [PATCH 30/30] microblaze_mmu_v1: fcntl.h " monstr
2009-04-27 9:59 ` Christoph Hellwig
2009-04-27 10:05 ` John Williams
2009-04-27 10:56 ` Michal Simek
2009-04-27 9:58 ` [PATCH 29/30] microblaze_mmu_v1: stat.h " Christoph Hellwig
2009-04-27 10:35 ` Michal Simek
2009-04-27 11:30 ` Christoph Hellwig
2009-04-27 11:43 ` Michal Simek
2009-04-27 11:57 ` Arnd Bergmann
2009-04-27 12:15 ` Sam Ravnborg
2009-04-27 12:37 ` Arnd Bergmann
2009-04-27 12:48 ` Sam Ravnborg
2009-04-27 12:55 ` Arnd Bergmann
2009-04-27 12:31 ` Michal Simek
2009-04-27 12:42 ` Arnd Bergmann
2009-04-27 12:44 ` Michal Simek
2009-04-27 12:47 ` Arnd Bergmann
2009-04-27 12:48 ` Michal Simek
2009-04-30 13:53 ` Arnd Bergmann
2009-04-30 14:10 ` Michal Simek
2009-04-30 14:40 ` Arnd Bergmann
2009-04-30 14:51 ` Michal Simek
2009-04-27 12:53 ` Arnd Bergmann
2009-04-27 13:03 ` Michal Simek
2009-04-27 13:13 ` Arnd Bergmann
2009-04-27 11:43 ` [PATCH 23/30] microblaze_mmu_v1: Enable fork syscall for MMU and add fork as vfork for noMMU John Williams
2009-04-29 10:16 ` Michal Simek
2009-04-29 11:31 ` Arnd Bergmann
2009-04-29 11:27 ` [PATCH 22/30] microblaze_mmu_v1: Update linker script for MMU Arnd Bergmann
2009-04-29 11:39 ` Michal Simek
2009-04-29 5:54 ` [PATCH 21/30] microblaze_mmu_v1: Add MMU related exceptions handling Andrew Morton
2009-04-29 9:36 ` Michal Simek
2009-04-29 5:53 ` [PATCH 20/30] microblaze_mmu_v1: uaccess MMU update Andrew Morton
2009-04-29 10:12 ` Michal Simek
2009-04-29 10:58 ` Arnd Bergmann
2009-04-29 15:19 ` Michal Simek
2009-04-29 15:35 ` Arnd Bergmann
2009-04-29 15:43 ` Michal Simek
2009-04-29 15:55 ` Arnd Bergmann [this message]
2009-04-29 11:26 ` Arnd Bergmann
2009-04-27 10:55 ` [PATCH 10/30] microblaze_mmu_v1: Context handling - mmu_context.c/h Arnd Bergmann
2009-04-27 11:18 ` Geert Uytterhoeven
2009-04-29 5:46 ` [PATCH 09/30] microblaze_mmu_v1: Page fault handling high level - fault.c Andrew Morton
2009-04-29 9:30 ` Michal Simek
2009-04-29 5:44 ` [PATCH 08/30] microblaze_mmu_v1: mmu.h update Andrew Morton
2009-04-29 9:28 ` Michal Simek
2009-04-29 5:42 ` [PATCH 07/30] microblaze_mmu_v1: MMU initialization Andrew Morton
2009-04-29 7:02 ` Michal Simek
2009-04-29 8:42 ` Michal Simek
2009-04-27 10:50 ` [PATCH 01/30] microblaze_mmu_v1: Makefiles Arnd Bergmann
2009-04-27 10:54 ` Michal Simek
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=200904291755.38497.arnd@arndb.de \
--to=arnd@arndb.de \
--cc=akpm@linux-foundation.org \
--cc=john.williams@petalogix.com \
--cc=linux-kernel@vger.kernel.org \
--cc=monstr@monstr.eu \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox