Re: [PATCH] memblock: Add limit checking to memblock_virt_alloc

[Yinghai Lu]

On Wed, Jan 29, 2014 at 3:39 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> On Wed, Jan 29, 2014 at 3:07 PM, Tony Luck <tony.luck@xxxxxxxxx> wrote:
>> Hmmph.  ia64 is broken too.  git bisect says:
>>
>> commit ad6492b80f60a2139fa9bf8fd79b182fe5e3647c
>> Author: Yinghai Lu <yinghai@xxxxxxxxxx>
>> Date:   Mon Jan 27 17:06:49 2014 -0800
>>
>>     memblock, nobootmem: add memblock_virt_alloc_low()
>>
>> is to blame.  But this patch doesn't fix it.  Still dies with:
>>
>> PID hash table entries: 4096 (order: -1, 32768 bytes)
>> Sorting __ex_table...
>> kernel BUG at mm/bootmem.c:504!
>
> that's another path with memblock_virt wrapper for bootmem.

Please check attached patch.

Thanks

Yinghai
Subject: [PATCH] memblock, bootmem: Restore goal for alloc_low

Now we have memblock_virt_alloc_low to replace original bootmem api
in swiotlb.

But we should not use BOOTMEM_LOW_LIMIT for arch that does not support
CONFIG_NOBOOTMEM, as old api take 0.

| #define alloc_bootmem_low(x) \
|        __alloc_bootmem_low(x, SMP_CACHE_BYTES, 0)
|#define alloc_bootmem_low_pages_nopanic(x) \
|        __alloc_bootmem_low_nopanic(x, PAGE_SIZE, 0)

and we have
 #define BOOTMEM_LOW_LIMIT __pa(MAX_DMA_ADDRESS)
for CONFIG_NOBOOTMEM.

Restore goal to 0 to fix ia64 crash, that Tony found.


Reported-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>

---
 include/linux/bootmem.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Index: linux-2.6/include/linux/bootmem.h
===================================================================
--- linux-2.6.orig/include/linux/bootmem.h
+++ linux-2.6/include/linux/bootmem.h
@@ -264,7 +264,7 @@ static inline void * __init memblock_vir
 {
 	if (!align)
 		align = SMP_CACHE_BYTES;
-	return __alloc_bootmem_low(size, align, BOOTMEM_LOW_LIMIT);
+	return __alloc_bootmem_low(size, align, 0);
 }
 
 static inline void * __init memblock_virt_alloc_low_nopanic(
@@ -272,7 +272,7 @@ static inline void * __init memblock_vir
 {
 	if (!align)
 		align = SMP_CACHE_BYTES;
-	return __alloc_bootmem_low_nopanic(size, align, BOOTMEM_LOW_LIMIT);
+	return __alloc_bootmem_low_nopanic(size, align, 0);
 }
 
 static inline void * __init memblock_virt_alloc_from_nopanic(