lkml.org 
[lkml]   [2019]   [Aug]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.2 049/144] powerpc: fix off by one in max_zone_pfn initialization for ZONE_DMA
Date
[ Upstream commit 03800e0526ee25ed7c843ca1e57b69ac2a5af642 ]

25078dc1f74be16b858e914f52cc8f4d03c2271a first introduced an off by
one error in the ZONE_DMA initialization of PPC_BOOK3E_64=y and since
9739ab7eda459f0669ec9807e0d9be5020bab88c the off by one applies to
PPC32=y too. This simply corrects the off by one and should resolve
crashes like below:

[ 65.179101] page 0x7fff outside node 0 zone DMA [ 0x0 - 0x7fff ]

Unfortunately in various MM places "max" means a non inclusive end of
range. free_area_init_nodes max_zone_pfn parameter is one case and
MAX_ORDER is another one (unrelated) that comes by memory.

Reported-by: Zorro Lang <zlang@redhat.com>
Fixes: 25078dc1f74b ("powerpc: use mm zones more sensibly")
Fixes: 9739ab7eda45 ("powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190625141727.2883-1-aarcange@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/mm/mem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 2540d3b2588c3..2eda1ec36f552 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -249,7 +249,7 @@ void __init paging_init(void)

#ifdef CONFIG_ZONE_DMA
max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
- ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
+ 1UL << (ARCH_ZONE_DMA_BITS - PAGE_SHIFT));
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
#ifdef CONFIG_HIGHMEM
--
2.20.1


\
 
 \ /
  Last update: 2019-08-14 19:05    [W:1.363 / U:0.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site