Re: Linux-2.4.20-pre8-aa2 oops report.

[Srihari Vijayaraghavan <harisri@bigpond.com>]

On Saturday 05 October 2002 12:47, Srihari Vijayaraghavan wrote:
> [1.] One line summary of the problem:
> 	2.4.20-pre8aa2 Kernel oopsed couple of times.

A little more research reveals that the oops happens at the following function 
in mm/memory.c

/*
 * remove user pages in a given range.
 */
void zap_page_range(struct mm_struct *mm, unsigned long address, unsigned long 
size)
{
	mmu_gather_t *tlb;
	pgd_t * dir;
	unsigned long start = address, end = address + size;
	int freed = 0;

	dir = pgd_offset(mm, address);

	/*
	 * This is a long-lived spinlock. That's fine.
	 * There's no contention, because the page table
	 * lock only protects against kswapd anyway, and
	 * even if kswapd happened to be looking at this
	 * process we _want_ it to get stuck.
	 */
	if (address >= end)
		BUG();
	spin_lock(&mm->page_table_lock);
	flush_cache_range(mm, address, end);
	tlb = tlb_gather_mmu(mm);

	do {
		freed += zap_pmd_range(tlb, dir, address, end - address);
		address = (address + PGDIR_SIZE) & PGDIR_MASK;
		dir++;
	} while (address && (address < end));

	/* this will flush any remaining tlb entries */
	tlb_finish_mmu(tlb, start, end);

	/*
	 * Update rss for the mm_struct (not necessarily current->mm)
	 * Notice that rss is an unsigned long.
	 */
	if (mm->rss > freed)
		mm->rss -= freed;
	else
		mm->rss = 0;
	spin_unlock(&mm->page_table_lock);
}

BTW I ran memtest2.x and memtest3.0 overnight few times in the past and it 
always passed for more than 30 times or so everytime. I forgot to mention 
this in my previous e-mail.
-- 
Hari
harisri@bigpond.com