public inbox for linux-arm-kernel@lists.infradead.org
 help / color / mirror / Atom feed
* [PATCH] ARM: mm: Fix the memblock allocation for LPAE machines
@ 2014-02-01 20:14 Santosh Shilimkar
  2014-02-05 23:39 ` Santosh Shilimkar
  0 siblings, 1 reply; 6+ messages in thread
From: Santosh Shilimkar @ 2014-02-01 20:14 UTC (permalink / raw)
  To: linux-arm-kernel

Commit ad6492b8 added much needed memblock_virt_alloc_low() and further
commit 07bacb3 {memblock, bootmem: restore goal for alloc_low} fixed the
issue with low memory limit thansk to Yinghai. But even after all these fixes,
there is still one case where the limit check done with ARCH_LOW_ADDRESS_LIMIT
for low memory fails. Russell pointed out the issue with 32 bit LPAE machines
in below thread.
	https://lkml.org/lkml/2014/1/28/364

Since on some LPAE machines where memory start address is beyond 4GB,
the low memory marker in memblock will be set to default
ARCH_LOW_ADDRESS_LIMIT which is wrong. We can fix this by letting
architectures set the ARCH_LOW_ADDRESS_LIMIT using another export
similar to memblock_set_current_limit() but am not sure whether
its worth the trouble. Tell me if you think otherwise.

Rather am just trying to fix that one broken case using memblock_virt_alloc()
in setup code since the memblock.current_limit is updated appropriately
makes it work on all ARM 32 bit machines.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Strashko, Grygorii <grygorii.strashko@ti.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
---
 arch/arm/kernel/setup.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index b0df976..1e8b030 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -731,7 +731,7 @@ static void __init request_standard_resources(const struct machine_desc *mdesc)
 	kernel_data.end     = virt_to_phys(_end - 1);
 
 	for_each_memblock(memory, region) {
-		res = memblock_virt_alloc_low(sizeof(*res), 0);
+		res = memblock_virt_alloc(sizeof(*res), 0);
 		res->name  = "System RAM";
 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
-- 
1.7.9.5

^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2014-02-06 18:51 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-02-01 20:14 [PATCH] ARM: mm: Fix the memblock allocation for LPAE machines Santosh Shilimkar
2014-02-05 23:39 ` Santosh Shilimkar
2014-02-05 23:48   ` Russell King - ARM Linux
2014-02-06  0:50     ` Santosh Shilimkar
2014-02-06 18:41       ` Russell King - ARM Linux
2014-02-06 18:51         ` Santosh Shilimkar

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox