[#4948] SHM does not work with MPU turned on

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[#4948] SHM does not work with MPU turned on

Submitted By: Mike Frysinger

Open Date

2009-03-02 11:38:22     Close Date

2009-04-08 22:12:03

Priority:

Medium     Assignee:

Graf Yang

Status:

Closed     Fixed In Release:

N/A

Found In Release:

snaps     Release:

Category:

N/A     Board:

N/A

Processor:

BF526     Silicon Revision:

Is this bug repeatable?:

Yes     Resolution:

Fixed

Uboot version or rev.:

    Toolchain version or rev.:

trunk

App binary format:

N/A     

Summary: SHM does not work with MPU turned on

Details:

 

thread details and simple test case here (i havent verified):

  blackfin.uclinux.org/gf/project/uclinux-dist/forum/?action=ForumBrowse&_forum_action=ForumMessageBrowse&thread_id=32758&forum_thread_style=threaded&forum_change_view=Change+view

 

Follow-ups

 

--- Mike Frysinger                                           2009-03-03 02:07:32

i'm attaching a cleaned up test case

 

to compile:

$ bfin-linux-uclibc-gcc -Wall shmtest.c -o shmtest

 

then on the board, run it twice ... first a reader then a writer, so might want

to login with telnet

$ shmtest r

$ shmtest w

 

now type somethings into the writer and it should show up in the reader

 

--- der knut                                                 2009-03-11 08:41:25

More info at

  blackfin.uclinux.org/gf/project/uclinux-dist/forum/?action=ForumBrowse&forum_id=39&_forum_action=ForumMessageBrowse&thread_id=32960

 

--- Michael Hennerich                                        2009-03-13 04:23:16

Graf,

 

FYI: According to Knut’s comments on the forum

- Enrik Berkhan and David Howells patch fixed this bug.

 

-Michael

 

--- Graf Yang                                                2009-03-13 05:41:07

Hi Michael,

 

Thanks! Seems Enrik's patch fixed Knut's problem. I will merge it to our

trunk.

 

The bug #4948 here is with MPU, still existed.

 

 

 

--- Graf Yang                                                2009-03-17 04:48:52

When protecting the pages for the new vma, the trail page is always not be

protected.

In shm case, the share memory is out of protection. Now it should be fixed.

 

 

 

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File Name     File Type     File Size     Posted By

shmtest.c    text/x-csrc    1232    Mike Frysinger

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