From 3bcfeaf93f44112053e1c36aa681d9efc1185ddc Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Thu, 20 Oct 2011 21:24:30 +0200 Subject: [PATCH] block: initialize the bounce pool if high memory may be added later init_emergency_pool() does not create the page pool for bouncing block requests if the current count of high pages is zero. If high memory may be added later (either via memory hotplug or a balloon driver in a virtualized system) then a oops occurs if a request with a high page need bouncing because the pool does not exist. So, always create the pool if memory hotplug is enabled and change the test so it's valid even if all high pages are currently in the balloon (the balloon drivers adjust totalhigh_pages but not max_pfn). Signed-off-by: David Vrabel Signed-off-by: Jens Axboe --- mm/bounce.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/mm/bounce.c b/mm/bounce.c index 1481de68184b..434fb4f0c5e4 100644 --- a/mm/bounce.c +++ b/mm/bounce.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -26,12 +27,10 @@ static mempool_t *page_pool, *isa_page_pool; #ifdef CONFIG_HIGHMEM static __init int init_emergency_pool(void) { - struct sysinfo i; - si_meminfo(&i); - si_swapinfo(&i); - - if (!i.totalhigh) +#ifndef CONFIG_MEMORY_HOTPLUG + if (max_pfn <= max_low_pfn) return 0; +#endif page_pool = mempool_create_page_pool(POOL_SIZE, 0); BUG_ON(!page_pool);