From 949e51bea342da838be5295628e4a7ada8bae833 Mon Sep 17 00:00:00 2001 From: David Daney Date: Thu, 14 Oct 2010 11:32:33 -0700 Subject: MIPS: Make TASK_SIZE reflect proper size for both 32 and 64 bit processes. The TASK_SIZE macro should reflect the size of a user process virtual address space. Previously for 64-bit kernels, this was not the case. The immediate cause of pain was in hugetlbfs/inode.c:hugetlb_get_unmapped_area() where 32-bit processes trying to mmap a huge page would be served a page with an address outside of the 32-bit address range. But there are other uses of TASK_SIZE in the kernel as well that would like an accurate value. The new definition is nice because it now makes TASK_SIZE and TASK_SIZE_OF() yield the same value for any given process. For 32-bit kernels there should be no change, although I did factor out some code in asm/processor.h that became identical for the 32-bit and 64-bit cases. __UA_LIMIT is now set to ~((1 << SEGBITS) - 1) for 64-bit kernels. This should eliminate the possibility of getting a AddressErrorException in the kernel for addresses that pass the access_ok() test. With the patch applied, I can still run o32, n32 and n64 processes, and have an o32 shell fork/exec both n32 and n64 processes. Signed-off-by: David Daney To: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/1701/ --- arch/mips/include/asm/uaccess.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/mips/include/asm/uaccess.h') diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h index c2d53c18fd36..653a412c036c 100644 --- a/arch/mips/include/asm/uaccess.h +++ b/arch/mips/include/asm/uaccess.h @@ -35,7 +35,9 @@ #ifdef CONFIG_64BIT -#define __UA_LIMIT (- TASK_SIZE) +extern u64 __ua_limit; + +#define __UA_LIMIT __ua_limit #define __UA_ADDR ".dword" #define __UA_LA "dla" -- cgit v1.2.3