From 4a20799d11f64e6b8725cacc7619b1ae1dbf9acd Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Tue, 14 Apr 2015 15:48:27 -0700 Subject: mm: move memtest under mm Memtest is a simple feature which fills the memory with a given set of patterns and validates memory contents, if bad memory regions is detected it reserves them via memblock API. Since memblock API is widely used by other architectures this feature can be enabled outside of x86 world. This patch set promotes memtest to live under generic mm umbrella and enables memtest feature for arm/arm64. It was reported that this patch set was useful for tracking down an issue with some errant DMA on an arm64 platform. This patch (of 6): There is nothing platform dependent in the core memtest code, so other platforms might benefit from this feature too. [linux@roeck-us.net: MEMTEST depends on MEMBLOCK] Signed-off-by: Vladimir Murzin Acked-by: Will Deacon Tested-by: Mark Rutland Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Catalin Marinas Cc: Russell King Cc: Paul Bolle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memtest.c | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 mm/memtest.c (limited to 'mm/memtest.c') diff --git a/mm/memtest.c b/mm/memtest.c new file mode 100644 index 000000000000..1e9da795767a --- /dev/null +++ b/mm/memtest.c @@ -0,0 +1,118 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static u64 patterns[] __initdata = { + /* The first entry has to be 0 to leave memtest with zeroed memory */ + 0, + 0xffffffffffffffffULL, + 0x5555555555555555ULL, + 0xaaaaaaaaaaaaaaaaULL, + 0x1111111111111111ULL, + 0x2222222222222222ULL, + 0x4444444444444444ULL, + 0x8888888888888888ULL, + 0x3333333333333333ULL, + 0x6666666666666666ULL, + 0x9999999999999999ULL, + 0xccccccccccccccccULL, + 0x7777777777777777ULL, + 0xbbbbbbbbbbbbbbbbULL, + 0xddddddddddddddddULL, + 0xeeeeeeeeeeeeeeeeULL, + 0x7a6c7258554e494cULL, /* yeah ;-) */ +}; + +static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad) +{ + printk(KERN_INFO " %016llx bad mem addr %010llx - %010llx reserved\n", + (unsigned long long) pattern, + (unsigned long long) start_bad, + (unsigned long long) end_bad); + memblock_reserve(start_bad, end_bad - start_bad); +} + +static void __init memtest(u64 pattern, u64 start_phys, u64 size) +{ + u64 *p, *start, *end; + u64 start_bad, last_bad; + u64 start_phys_aligned; + const size_t incr = sizeof(pattern); + + start_phys_aligned = ALIGN(start_phys, incr); + start = __va(start_phys_aligned); + end = start + (size - (start_phys_aligned - start_phys)) / incr; + start_bad = 0; + last_bad = 0; + + for (p = start; p < end; p++) + *p = pattern; + + for (p = start; p < end; p++, start_phys_aligned += incr) { + if (*p == pattern) + continue; + if (start_phys_aligned == last_bad + incr) { + last_bad += incr; + continue; + } + if (start_bad) + reserve_bad_mem(pattern, start_bad, last_bad + incr); + start_bad = last_bad = start_phys_aligned; + } + if (start_bad) + reserve_bad_mem(pattern, start_bad, last_bad + incr); +} + +static void __init do_one_pass(u64 pattern, u64 start, u64 end) +{ + u64 i; + phys_addr_t this_start, this_end; + + for_each_free_mem_range(i, NUMA_NO_NODE, &this_start, &this_end, NULL) { + this_start = clamp_t(phys_addr_t, this_start, start, end); + this_end = clamp_t(phys_addr_t, this_end, start, end); + if (this_start < this_end) { + printk(KERN_INFO " %010llx - %010llx pattern %016llx\n", + (unsigned long long)this_start, + (unsigned long long)this_end, + (unsigned long long)cpu_to_be64(pattern)); + memtest(pattern, this_start, this_end - this_start); + } + } +} + +/* default is disabled */ +static int memtest_pattern __initdata; + +static int __init parse_memtest(char *arg) +{ + if (arg) + memtest_pattern = simple_strtoul(arg, NULL, 0); + else + memtest_pattern = ARRAY_SIZE(patterns); + + return 0; +} + +early_param("memtest", parse_memtest); + +void __init early_memtest(unsigned long start, unsigned long end) +{ + unsigned int i; + unsigned int idx = 0; + + if (!memtest_pattern) + return; + + printk(KERN_INFO "early_memtest: # of tests: %d\n", memtest_pattern); + for (i = memtest_pattern-1; i < UINT_MAX; --i) { + idx = i % ARRAY_SIZE(patterns); + do_one_pass(patterns[idx], start, end); + } +} -- cgit v1.2.3 From 7f70baeeb9e2d2b2a37a4bd3727d709547c4ae41 Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Tue, 14 Apr 2015 15:48:30 -0700 Subject: memtest: use phys_addr_t for physical addresses Since memtest might be used by other architectures pass input parameters as phys_addr_t instead of long to prevent overflow. Signed-off-by: Vladimir Murzin Acked-by: Will Deacon Tested-by: Mark Rutland Cc: "H. Peter Anvin" Cc: Catalin Marinas Cc: Ingo Molnar Cc: Russell King Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memblock.h | 4 ++-- mm/memtest.c | 16 ++++++++-------- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'mm/memtest.c') diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 6724cb020f5e..9497ec7c77ea 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -366,9 +366,9 @@ static inline unsigned long memblock_region_reserved_end_pfn(const struct memblo #endif #ifdef CONFIG_MEMTEST -extern void early_memtest(unsigned long start, unsigned long end); +extern void early_memtest(phys_addr_t start, phys_addr_t end); #else -static inline void early_memtest(unsigned long start, unsigned long end) +static inline void early_memtest(phys_addr_t start, phys_addr_t end) { } #endif diff --git a/mm/memtest.c b/mm/memtest.c index 1e9da795767a..1997d934b13b 100644 --- a/mm/memtest.c +++ b/mm/memtest.c @@ -29,7 +29,7 @@ static u64 patterns[] __initdata = { 0x7a6c7258554e494cULL, /* yeah ;-) */ }; -static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad) +static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr_t end_bad) { printk(KERN_INFO " %016llx bad mem addr %010llx - %010llx reserved\n", (unsigned long long) pattern, @@ -38,11 +38,11 @@ static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad) memblock_reserve(start_bad, end_bad - start_bad); } -static void __init memtest(u64 pattern, u64 start_phys, u64 size) +static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size) { u64 *p, *start, *end; - u64 start_bad, last_bad; - u64 start_phys_aligned; + phys_addr_t start_bad, last_bad; + phys_addr_t start_phys_aligned; const size_t incr = sizeof(pattern); start_phys_aligned = ALIGN(start_phys, incr); @@ -69,14 +69,14 @@ static void __init memtest(u64 pattern, u64 start_phys, u64 size) reserve_bad_mem(pattern, start_bad, last_bad + incr); } -static void __init do_one_pass(u64 pattern, u64 start, u64 end) +static void __init do_one_pass(u64 pattern, phys_addr_t start, phys_addr_t end) { u64 i; phys_addr_t this_start, this_end; for_each_free_mem_range(i, NUMA_NO_NODE, &this_start, &this_end, NULL) { - this_start = clamp_t(phys_addr_t, this_start, start, end); - this_end = clamp_t(phys_addr_t, this_end, start, end); + this_start = clamp(this_start, start, end); + this_end = clamp(this_end, start, end); if (this_start < this_end) { printk(KERN_INFO " %010llx - %010llx pattern %016llx\n", (unsigned long long)this_start, @@ -102,7 +102,7 @@ static int __init parse_memtest(char *arg) early_param("memtest", parse_memtest); -void __init early_memtest(unsigned long start, unsigned long end) +void __init early_memtest(phys_addr_t start, phys_addr_t end) { unsigned int i; unsigned int idx = 0; -- cgit v1.2.3