From 7e01b5acd88b3f3108d8c4ce44e3205d67437202 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Thu, 16 Apr 2015 14:47:33 +0200 Subject: [PATCH] kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP Introduce KEXEC_CONTROL_MEMORY_GFP to allow the architecture code to override the gfp flags of the allocation for the kexec control page. The loop in kimage_alloc_normal_control_pages allocates pages with GFP_KERNEL until a page is found that happens to have an address smaller than the KEXEC_CONTROL_MEMORY_LIMIT. On systems with a large memory size but a small KEXEC_CONTROL_MEMORY_LIMIT the loop will keep allocating memory until the oom killer steps in. Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/kexec.h | 3 +++ include/linux/kexec.h | 4 ++++ kernel/kexec.c | 2 +- 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/s390/include/asm/kexec.h b/arch/s390/include/asm/kexec.h index 694bcd6..2f924bc 100644 --- a/arch/s390/include/asm/kexec.h +++ b/arch/s390/include/asm/kexec.h @@ -26,6 +26,9 @@ /* Not more than 2GB */ #define KEXEC_CONTROL_MEMORY_LIMIT (1UL<<31) +/* Allocate control page with GFP_DMA */ +#define KEXEC_CONTROL_MEMORY_GFP GFP_DMA + /* Maximum address we can use for the crash control pages */ #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT (-1UL) diff --git a/include/linux/kexec.h b/include/linux/kexec.h index e60a745..e804306 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -40,6 +40,10 @@ #error KEXEC_CONTROL_MEMORY_LIMIT not defined #endif +#ifndef KEXEC_CONTROL_MEMORY_GFP +#define KEXEC_CONTROL_MEMORY_GFP GFP_KERNEL +#endif + #ifndef KEXEC_CONTROL_PAGE_SIZE #error KEXEC_CONTROL_PAGE_SIZE not defined #endif diff --git a/kernel/kexec.c b/kernel/kexec.c index 38c25b1..7a36fdc 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -707,7 +707,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image, do { unsigned long pfn, epfn, addr, eaddr; - pages = kimage_alloc_pages(GFP_KERNEL, order); + pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order); if (!pages) break; pfn = page_to_pfn(pages); -- 2.7.4