From: Alexander Stein Date: Tue, 10 Jan 2012 13:06:07 +0000 (+0100) Subject: m68k: Add shared bit to Coldfire kernel page entries X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=57e00098cc0e43d001c9c8a018a1f8396faa0d16;p=mv-sheeva.git m68k: Add shared bit to Coldfire kernel page entries We had problems accessing our NOR flash trough mtd. The system always got stuck at attaching UBI using ubiattach if booted from NFS or after mounting squashfs as rootfs directly from NOR flash. After some testing of the new changes introduced from v3.2-rc1 to v3.2-rc7 we had to apply the following patch to get mtd working again. [gerg: The problem was ultimately caused by allocated kernel pages not having the shared (SG) bit set. Without the SG bit set the MMU will look for page matches incorporating the ASID as well. Things like module regions allocated using vmalloc would fault when other processes run. ] Signed-off-by: Alexander Stein Signed-off-by: Greg Ungerer --- diff --git a/arch/m68k/include/asm/mcf_pgtable.h b/arch/m68k/include/asm/mcf_pgtable.h index 756bde4fb4f..3c793682e5d 100644 --- a/arch/m68k/include/asm/mcf_pgtable.h +++ b/arch/m68k/include/asm/mcf_pgtable.h @@ -78,7 +78,8 @@ | CF_PAGE_READABLE \ | CF_PAGE_WRITABLE \ | CF_PAGE_EXEC \ - | CF_PAGE_SYSTEM) + | CF_PAGE_SYSTEM \ + | CF_PAGE_SHARED) #define PAGE_COPY __pgprot(CF_PAGE_VALID \ | CF_PAGE_ACCESSED \