lkml.org 
[lkml]   [2008]   [Jan]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
SubjectRe: 2.6.24-rc8-mm1: powerpc oopses
From
Date

On Thu, 2008-01-17 at 16:29 -0800, Andrew Morton wrote:
> Do we need `offset' at all?

Looks like no.

I wonder if there's a good argument for adding a pte_offset_val() which
would let us do:

pteval = pte_offset_val(pmd, addr);

and shrink the map/unmap window and overhead here and possibly
elsewhere?

Anyway, updated but still untested patch now with revealing comment:

diff -r 5595adaea70f fs/proc/task_mmu.c
--- a/fs/proc/task_mmu.c Thu Jan 17 13:26:54 2008 -0600
+++ b/fs/proc/task_mmu.c Thu Jan 17 18:45:57 2008 -0600
@@ -584,18 +585,19 @@
pte_t *pte;
int err = 0;

- pte = pte_offset_map(pmd, addr);
- for (; addr != end; pte++, addr += PAGE_SIZE) {
+ for (; addr != end; addr += PAGE_SIZE) {
u64 pfn = PM_NOT_PRESENT;
+ pte = pte_offset_map(pmd, addr);
if (is_swap_pte(*pte))
pfn = swap_pte_to_pagemap_entry(*pte);
else if (pte_present(*pte))
pfn = pte_pfn(*pte);
+ /* unmap so we're not in atomic when we copy to userspace */
+ pte_unmap(pte);
err = add_to_pagemap(addr, pfn, pm);
if (err)
return err;
}
- pte_unmap(pte - 1);

cond_resched();


--
Mathematics is the supreme nostalgia of our time.



\
 
 \ /
  Last update: 2008-01-18 01:51    [W:0.139 / U:0.968 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site