mm: enhance free_reserved_area() to support poisoning memory with zero Address more review comments from last round of code review. 1) Enhance free_reserved_area() to support poisoning freed memory with pattern '0'. This could be used to get rid of poison_init_mem() on ARM64. 2) A previous patch has disabled memory poison for initmem on s390 by mistake, so restore to the original behavior. 3) Remove redundant PAGE_ALIGN() when calling free_reserved_area(). Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michel Lespinasse <walken@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c index 891bd27..837c0fa 100644 --- a/arch/alpha/kernel/sys_nautilus.c +++ b/arch/alpha/kernel/sys_nautilus.c
@@ -239,7 +239,7 @@ memtop = pci_mem; if (memtop > alpha_mv.min_mem_address) { free_reserved_area(__va(alpha_mv.min_mem_address), - __va(memtop), 0, NULL); + __va(memtop), -1, NULL); printk("nautilus_init_pci: %ldk freed\n", (memtop - alpha_mv.min_mem_address) >> 10); }
diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c index d54848d..218c29c 100644 --- a/arch/alpha/mm/init.c +++ b/arch/alpha/mm/init.c
@@ -319,13 +319,13 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index dce02e4..f9c7077 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c
@@ -146,13 +146,13 @@ */ void __init_refok free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD void __init free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 7fae391..2070651 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c
@@ -601,7 +601,7 @@ #ifdef CONFIG_SA1111 /* now that our DMA memory is actually so designated, we can free it */ - free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL); + free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, -1, NULL); #endif free_highpages(); @@ -729,12 +729,12 @@ extern char __tcm_start, __tcm_end; poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start); - free_reserved_area(&__tcm_start, &__tcm_end, 0, "TCM link"); + free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link"); #endif poison_init_mem(__init_begin, __init_end - __init_begin); if (!machine_is_integrator() && !machine_is_cintegrator()) - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD @@ -745,7 +745,7 @@ { if (!keep_initrd) { poison_init_mem((void *)start, PAGE_ALIGN(end) - start); - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } }
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 6041e40..997c634 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c
@@ -387,7 +387,7 @@ void free_initmem(void) { poison_init_mem(__init_begin, __init_end - __init_begin); - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD @@ -398,7 +398,7 @@ { if (!keep_initrd) { poison_init_mem((void *)start, PAGE_ALIGN(end) - start); - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } }
diff --git a/arch/avr32/mm/init.c b/arch/avr32/mm/init.c index 5a79fa0..b079e04 100644 --- a/arch/avr32/mm/init.c +++ b/arch/avr32/mm/init.c
@@ -148,12 +148,12 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/blackfin/mm/init.c b/arch/blackfin/mm/init.c index 8e9eab2..fa241f5 100644 --- a/arch/blackfin/mm/init.c +++ b/arch/blackfin/mm/init.c
@@ -133,7 +133,7 @@ void __init free_initrd_mem(unsigned long start, unsigned long end) { #ifndef CONFIG_MPU - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); #endif } #endif @@ -141,7 +141,7 @@ void __init_refok free_initmem(void) { #if defined CONFIG_RAMKERNEL && !defined CONFIG_MPU - free_initmem_default(0); + free_initmem_default(-1); if (memory_start == (unsigned long)(&__init_end)) memory_start = (unsigned long)(&__init_begin); #endif
diff --git a/arch/c6x/mm/init.c b/arch/c6x/mm/init.c index 07bfcc9..3987a20 100644 --- a/arch/c6x/mm/init.c +++ b/arch/c6x/mm/init.c
@@ -78,11 +78,11 @@ #ifdef CONFIG_BLK_DEV_INITRD void __init free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif void __init free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); }
diff --git a/arch/cris/mm/init.c b/arch/cris/mm/init.c index 9ac8094..8fec263 100644 --- a/arch/cris/mm/init.c +++ b/arch/cris/mm/init.c
@@ -65,5 +65,5 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); }
diff --git a/arch/frv/mm/init.c b/arch/frv/mm/init.c index a67f3a5..8ba9d22 100644 --- a/arch/frv/mm/init.c +++ b/arch/frv/mm/init.c
@@ -162,7 +162,7 @@ void free_initmem(void) { #if defined(CONFIG_RAMKERNEL) && !defined(CONFIG_PROTECT_KERNEL) - free_initmem_default(0); + free_initmem_default(-1); #endif } /* end free_initmem() */ @@ -173,6 +173,6 @@ #ifdef CONFIG_BLK_DEV_INITRD void __init free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } /* end free_initrd_mem() */ #endif
diff --git a/arch/h8300/mm/init.c b/arch/h8300/mm/init.c index 57e03c5..c831f1d 100644 --- a/arch/h8300/mm/init.c +++ b/arch/h8300/mm/init.c
@@ -161,7 +161,7 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif @@ -169,7 +169,7 @@ free_initmem(void) { #ifdef CONFIG_RAMKERNEL - free_initmem_default(0); + free_initmem_default(-1); #endif }
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index da568c2..f8a4f38 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c
@@ -155,7 +155,7 @@ free_initmem (void) { free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end), - 0, "unused kernel"); + -1, "unused kernel"); } void __init
diff --git a/arch/m32r/mm/init.c b/arch/m32r/mm/init.c index d80412d..cca87d9 100644 --- a/arch/m32r/mm/init.c +++ b/arch/m32r/mm/init.c
@@ -181,7 +181,7 @@ *======================================================================*/ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD @@ -191,6 +191,6 @@ *======================================================================*/ void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c index 95de725..ab0b54c 100644 --- a/arch/m68k/mm/init.c +++ b/arch/m68k/mm/init.c
@@ -110,7 +110,7 @@ void free_initmem(void) { #ifndef CONFIG_MMU_SUN3 - free_initmem_default(0); + free_initmem_default(-1); #endif /* CONFIG_MMU_SUN3 */ } @@ -202,6 +202,6 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c index d7b8ada9..d149e0e 100644 --- a/arch/microblaze/mm/init.c +++ b/arch/microblaze/mm/init.c
@@ -235,13 +235,13 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } void __init mem_init(void)
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c index ab113325..c371e4a 100644 --- a/arch/openrisc/mm/init.c +++ b/arch/openrisc/mm/init.c
@@ -261,11 +261,11 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); }
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index 3223d5e..ebac7bd 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c
@@ -532,7 +532,7 @@ * pages are no-longer executable */ flush_icache_range(init_begin, init_end); - num_physpages += free_initmem_default(0); + num_physpages += free_initmem_default(-1); /* set up a new led state on systems shipped LED State panel */ pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE); @@ -1101,7 +1101,7 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - num_physpages += free_reserved_area((void *)start, (void *)end, 0, + num_physpages += free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c index 5e4830a3..db28032 100644 --- a/arch/powerpc/kernel/kvm.c +++ b/arch/powerpc/kernel/kvm.c
@@ -750,13 +750,8 @@ static __init void kvm_free_tmp(void) { - unsigned long start, end; - - start = (ulong)&kvm_tmp[kvm_tmp_index + (PAGE_SIZE - 1)] & PAGE_MASK; - end = (ulong)&kvm_tmp[ARRAY_SIZE(kvm_tmp)] & PAGE_MASK; - - /* Free the tmp space we don't need */ - free_reserved_area((void *)start, (void *)end, 0, NULL); + free_reserved_area(&kvm_tmp[kvm_tmp_index], + &kvm_tmp[ARRAY_SIZE(kvm_tmp)], -1, NULL); } static int __init kvm_guest_init(void)
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 347c5b1..7f47a05 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c
@@ -407,7 +407,7 @@ #ifdef CONFIG_BLK_DEV_INITRD void __init free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 0878c89..bf01d18 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c
@@ -166,7 +166,7 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(POISON_FREE_INITMEM); } #ifdef CONFIG_BLK_DEV_INITRD
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c index b892a9b..d3af56b 100644 --- a/arch/sh/mm/init.c +++ b/arch/sh/mm/init.c
@@ -499,13 +499,13 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c index 2aa7a24..8ff0b7a 100644 --- a/arch/um/kernel/mem.c +++ b/arch/um/kernel/mem.c
@@ -244,7 +244,7 @@ #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif
diff --git a/arch/unicore32/mm/init.c b/arch/unicore32/mm/init.c index 220755c..df9b8ab 100644 --- a/arch/unicore32/mm/init.c +++ b/arch/unicore32/mm/init.c
@@ -476,7 +476,7 @@ void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD @@ -486,7 +486,7 @@ void free_initrd_mem(unsigned long start, unsigned long end) { if (!keep_initrd) - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } static int __init keepinitrd_setup(char *__unused)
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c index 4d658ef..026d29b 100644 --- a/arch/xtensa/mm/init.c +++ b/arch/xtensa/mm/init.c
@@ -214,11 +214,11 @@ void free_initrd_mem(unsigned long start, unsigned long end) { if (initrd_is_mapped) - free_reserved_area((void *)start, (void *)end, 0, "initrd"); + free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif void free_initmem(void) { - free_initmem_default(0); + free_initmem_default(-1); }
diff --git a/include/linux/mm.h b/include/linux/mm.h index be1b96ce..083cc0b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h
@@ -1308,7 +1308,7 @@ /* * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) * into the buddy system. The freed pages will be poisoned with pattern - * "poison" if it's non-zero. + * "poison" if it's within range [0, UCHAR_MAX]. * Return pages freed into the buddy system. */ extern unsigned long free_reserved_area(void *start, void *end, @@ -1348,8 +1348,9 @@ /* * Default method to free all the __init memory into the buddy system. - * The freed pages will be poisoned with pattern "poison" if it is - * non-zero. Return pages freed into the buddy system. + * The freed pages will be poisoned with pattern "poison" if it's within + * range [0, UCHAR_MAX]. + * Return pages freed into the buddy system. */ static inline unsigned long free_initmem_default(int poison) {
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index be18ccd..6780b2e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c
@@ -5214,7 +5214,7 @@ start = (void *)PAGE_ALIGN((unsigned long)start); end = (void *)((unsigned long)end & PAGE_MASK); for (pos = start; pos < end; pos += PAGE_SIZE, pages++) { - if (poison) + if ((unsigned int)poison <= 0xFF) memset(pos, poison, PAGE_SIZE); free_reserved_page(virt_to_page(pos)); }