2.4.21 from CVS is the first kernel to exhibit the problem. I tracked it down to the cache handling changes that went in between 2.4.20 and 2.4.21.
By (not very scientifically) removing flush_dcache_page() and re-instating flush_page_to_ram() I managed to get the 2.4.21 kernel stable (see attached patch). Applying a similiar patch to 2.4.23 (CVS HEAD) allows me to run 2.4.23 too.
I don't know how to track the problem any further - the kernel's cache handling is a bit out of my league.
Anyone got a clue stick they can point me in the right direction with ?
P.
diff -urN linux-2.4.21-xxx/arch/mips/mm/c-r4k.c linux-2.4.21/arch/mips/mm/c-r4k.c
--- linux-2.4.21-xxx/arch/mips/mm/c-r4k.c Thu Dec 11 20:20:28 2003
+++ linux-2.4.21/arch/mips/mm/c-r4k.c Thu Dec 11 10:02:54 2003
@@ -1037,16 +1037,6 @@
return 1;
}
-static void r4k_flush_page_to_ram_d16(struct page *page)
-{
- blast_dcache16_page((unsigned long)page_address(page));
-}
-
-static void r4k_flush_page_to_ram_d32(struct page *page)
-{
- blast_dcache32_page((unsigned long)page_address(page));
-}
-
static void __init setup_noscache_funcs(void)
{
unsigned int prid;
@@ -1059,7 +1049,6 @@
_clear_page = r4k_clear_page32_d16;
_copy_page = r4k_copy_page_d16;
- _flush_page_to_ram = r4k_flush_page_to_ram_d16;
break;
case 32:
prid = read_c0_prid() & 0xfff0;
@@ -1076,8 +1065,6 @@
_clear_page = r4k_clear_page32_d32;
_copy_page = r4k_copy_page_d32;
}
-
- _flush_page_to_ram = r4k_flush_page_to_ram_d32;
break;
}
}
diff -urN linux-2.4.21-xxx/arch/mips/mm/cache.c linux-2.4.21/arch/mips/mm/cache.c
--- linux-2.4.21-xxx/arch/mips/mm/cache.c Thu Dec 11 20:15:37 2003
+++ linux-2.4.21/arch/mips/mm/cache.c Fri Jul 18 15:16:06 2003
@@ -20,8 +20,6 @@
return 0;
}
-#if 0
-
void flush_dcache_page(struct page *page)
{
unsigned long addr;
@@ -67,5 +65,3 @@
}
EXPORT_SYMBOL(flush_dcache_page);
-
-#endif
diff -urN linux-2.4.21-xxx/arch/mips/mm/loadmmu.c linux-2.4.21/arch/mips/mm/loadmmu.c
--- linux-2.4.21-xxx/arch/mips/mm/loadmmu.c Thu Dec 11 20:25:23 2003
+++ linux-2.4.21/arch/mips/mm/loadmmu.c Thu Dec 11 10:02:54 2003
@@ -40,8 +40,6 @@
void (*_flush_data_cache_page)(unsigned long addr);
void (*_flush_icache_all)(void);
-void (*_flush_page_to_ram)(struct page * page);
-
#ifdef CONFIG_NONCOHERENT_IO
/* DMA cache operations. */
diff -urN linux-2.4.21-xxx/include/asm-mips/cacheflush.h linux-2.4.21/include/asm-mips/cacheflush.h
--- linux-2.4.21-xxx/include/asm-mips/cacheflush.h Thu Dec 11 20:22:51 2003
+++ linux-2.4.21/include/asm-mips/cacheflush.h Tue Apr 1 00:29:06 2003
@@ -46,16 +46,12 @@
extern void (*_flush_icache_all)(void);
extern void (*_flush_data_cache_page)(unsigned long addr);
-extern void (*_flush_page_to_ram)(struct page * page);
-
-#define flush_dcache_page(page) do { } while(0)
-
#define flush_cache_all() _flush_cache_all()
#define __flush_cache_all() ___flush_cache_all()
#define flush_cache_mm(mm) _flush_cache_mm(mm)
#define flush_cache_range(mm,start,end) _flush_cache_range(mm,start,end)
#define flush_cache_page(vma,page) _flush_cache_page(vma, page)
-#define flush_page_to_ram(page) _flush_page_to_ram(page)
+#define flush_page_to_ram(page) do { } while (0)
#define flush_icache_range(start, end) _flush_icache_range(start,end)
#define flush_icache_user_range(vma, page, addr, len) \
diff -urN linux-2.4.21-xxx/include/asm-mips/pgtable.h linux-2.4.21/include/asm-mips/pgtable.h
--- linux-2.4.21-xxx/include/asm-mips/pgtable.h Thu Dec 11 20:36:56 2003
+++ linux-2.4.21/include/asm-mips/pgtable.h Thu Dec 11 10:04:27 2003
@@ -261,7 +261,7 @@
unsigned long address, pte_t pte)
{
__update_tlb(vma, address, pte);
-// __update_cache(vma, address, pte);
+ __update_cache(vma, address, pte);
}
/* Swap entries must have VALID and GLOBAL bits cleared. */
