Commit-ID: d5c78673b1b28467354c2c30c3d4f003666ff385 Gitweb: http://git.kernel.org/tip/d5c78673b1b28467354c2c30c3d4f003666ff385 Author: Yinghai Lu <yinghai@xxxxxxxxxx> AuthorDate: Thu, 13 Jun 2013 15:33:35 -0700 Committer: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx> CommitDate: Tue, 25 Jun 2013 13:08:10 -0700 x86: Fix /proc/mtrr with base/size more than 44bits On one sytem that mtrr range is more then 44bits, in dmesg we have [ 0.000000] MTRR default type: write-back [ 0.000000] MTRR fixed ranges enabled: [ 0.000000] 00000-9FFFF write-back [ 0.000000] A0000-BFFFF uncachable [ 0.000000] C0000-DFFFF write-through [ 0.000000] E0000-FFFFF write-protect [ 0.000000] MTRR variable ranges enabled: [ 0.000000] 0 [000080000000-0000FFFFFFFF] mask 3FFF80000000 uncachable [ 0.000000] 1 [380000000000-38FFFFFFFFFF] mask 3F0000000000 uncachable [ 0.000000] 2 [000099000000-000099FFFFFF] mask 3FFFFF000000 write-through [ 0.000000] 3 [00009A000000-00009AFFFFFF] mask 3FFFFF000000 write-through [ 0.000000] 4 [381FFA000000-381FFBFFFFFF] mask 3FFFFE000000 write-through [ 0.000000] 5 [381FFC000000-381FFC0FFFFF] mask 3FFFFFF00000 write-through [ 0.000000] 6 [0000AD000000-0000ADFFFFFF] mask 3FFFFF000000 write-through [ 0.000000] 7 [0000BD000000-0000BDFFFFFF] mask 3FFFFF000000 write-through [ 0.000000] 8 disabled [ 0.000000] 9 disabled but /proc/mtrr report wrong: reg00: base=0x080000000 ( 2048MB), size= 2048MB, count=1: uncachable reg01: base=0x80000000000 (8388608MB), size=1048576MB, count=1: uncachable reg02: base=0x099000000 ( 2448MB), size= 16MB, count=1: write-through reg03: base=0x09a000000 ( 2464MB), size= 16MB, count=1: write-through reg04: base=0x81ffa000000 (8519584MB), size= 32MB, count=1: write-through reg05: base=0x81ffc000000 (8519616MB), size= 1MB, count=1: write-through reg06: base=0x0ad000000 ( 2768MB), size= 16MB, count=1: write-through reg07: base=0x0bd000000 ( 3024MB), size= 16MB, count=1: write-through reg08: base=0x09b000000 ( 2480MB), size= 16MB, count=1: write-combining so bit 44 and bit 45 get cut off. We have problems in arch/x86/kernel/cpu/mtrr/generic.c::generic_get_mtrr(). 1. for base, we miss cast base_lo to 64bit before shifting. Fix that by adding u64 casting. 2. for size, it only can handle 44 bits aka 32bits + page_shift Fix that with 64bit mask instead of 32bit mask_lo, then range could be more than 44bits. At the same time, we need to update size_or_mask for old cpus that does support cpuid 0x80000008 to get phys_addr. Need to set high 32bits to all 1s, otherwise will not get correct size for them. Also fix mtrr_add_page: it should check base and (base + size - 1) instead of base and size, as base and size could be small but base + size could bigger enough to be out of boundary. We can use boot_cpu_data.x86_phys_bits directly to avoid size_or_mask. So When are we going to have size more than 44bits? that is 16TiB. after patch we have right ouput: reg00: base=0x080000000 ( 2048MB), size= 2048MB, count=1: uncachable reg01: base=0x380000000000 (58720256MB), size=1048576MB, count=1: uncachable reg02: base=0x099000000 ( 2448MB), size= 16MB, count=1: write-through reg03: base=0x09a000000 ( 2464MB), size= 16MB, count=1: write-through reg04: base=0x381ffa000000 (58851232MB), size= 32MB, count=1: write-through reg05: base=0x381ffc000000 (58851264MB), size= 1MB, count=1: write-through reg06: base=0x0ad000000 ( 2768MB), size= 16MB, count=1: write-through reg07: base=0x0bd000000 ( 3024MB), size= 16MB, count=1: write-through reg08: base=0x09b000000 ( 2480MB), size= 16MB, count=1: write-combining -v2: simply checking in mtrr_add_page according to hpa. [ hpa: This probably wants to go into -stable only after having sat in mainline for a bit. It is not a regression. ] Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1371162815-29931-1-git-send-email-yinghai@xxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/mtrr/generic.c | 21 +++++++++++---------- arch/x86/kernel/cpu/mtrr/main.c | 16 +++++++++------- 2 files changed, 20 insertions(+), 17 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c index fa72a39..3982357 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -510,8 +510,9 @@ generic_get_free_region(unsigned long base, unsigned long size, int replace_reg) static void generic_get_mtrr(unsigned int reg, unsigned long *base, unsigned long *size, mtrr_type *type) { - unsigned int mask_lo, mask_hi, base_lo, base_hi; - unsigned int tmp, hi; + u32 mask_lo, mask_hi, base_lo, base_hi; + unsigned int hi; + u64 tmp, mask; /* * get_mtrr doesn't need to update mtrr_state, also it could be called @@ -532,18 +533,18 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base, rdmsr(MTRRphysBase_MSR(reg), base_lo, base_hi); /* Work out the shifted address mask: */ - tmp = mask_hi << (32 - PAGE_SHIFT) | mask_lo >> PAGE_SHIFT; - mask_lo = size_or_mask | tmp; + tmp = (u64)mask_hi << (32 - PAGE_SHIFT) | mask_lo >> PAGE_SHIFT; + mask = size_or_mask | tmp; /* Expand tmp with high bits to all 1s: */ - hi = fls(tmp); + hi = fls64(tmp); if (hi > 0) { - tmp |= ~((1<<(hi - 1)) - 1); + tmp |= ~((1ULL<<(hi - 1)) - 1); - if (tmp != mask_lo) { + if (tmp != mask) { printk(KERN_WARNING "mtrr: your BIOS has configured an incorrect mask, fixing it.\n"); add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); - mask_lo = tmp; + mask = tmp; } } @@ -551,8 +552,8 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base, * This works correctly if size is a power of two, i.e. a * contiguous range: */ - *size = -mask_lo; - *base = base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT; + *size = -mask; + *base = (u64)base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT; *type = base_lo & 0xff; out_put_cpu: diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 726bf96..ca22b73 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -305,7 +305,8 @@ int mtrr_add_page(unsigned long base, unsigned long size, return -EINVAL; } - if (base & size_or_mask || size & size_or_mask) { + if ((base | (base + size - 1)) >> + (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) { pr_warning("mtrr: base or size exceeds the MTRR width\n"); return -EINVAL; } @@ -583,6 +584,7 @@ static struct syscore_ops mtrr_syscore_ops = { int __initdata changed_by_mtrr_cleanup; +#define SIZE_OR_MASK_BITS(n) (~((1ULL << ((n) - PAGE_SHIFT)) - 1)) /** * mtrr_bp_init - initialize mtrrs on the boot CPU * @@ -600,7 +602,7 @@ void __init mtrr_bp_init(void) if (cpu_has_mtrr) { mtrr_if = &generic_mtrr_ops; - size_or_mask = 0xff000000; /* 36 bits */ + size_or_mask = SIZE_OR_MASK_BITS(36); size_and_mask = 0x00f00000; phys_addr = 36; @@ -619,7 +621,7 @@ void __init mtrr_bp_init(void) boot_cpu_data.x86_mask == 0x4)) phys_addr = 36; - size_or_mask = ~((1ULL << (phys_addr - PAGE_SHIFT)) - 1); + size_or_mask = SIZE_OR_MASK_BITS(phys_addr); size_and_mask = ~size_or_mask & 0xfffff00000ULL; } else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR && boot_cpu_data.x86 == 6) { @@ -627,7 +629,7 @@ void __init mtrr_bp_init(void) * VIA C* family have Intel style MTRRs, * but don't support PAE */ - size_or_mask = 0xfff00000; /* 32 bits */ + size_or_mask = SIZE_OR_MASK_BITS(32); size_and_mask = 0; phys_addr = 32; } @@ -637,21 +639,21 @@ void __init mtrr_bp_init(void) if (cpu_has_k6_mtrr) { /* Pre-Athlon (K6) AMD CPU MTRRs */ mtrr_if = mtrr_ops[X86_VENDOR_AMD]; - size_or_mask = 0xfff00000; /* 32 bits */ + size_or_mask = SIZE_OR_MASK_BITS(32); size_and_mask = 0; } break; case X86_VENDOR_CENTAUR: if (cpu_has_centaur_mcr) { mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR]; - size_or_mask = 0xfff00000; /* 32 bits */ + size_or_mask = SIZE_OR_MASK_BITS(32); size_and_mask = 0; } break; case X86_VENDOR_CYRIX: if (cpu_has_cyrix_arr) { mtrr_if = mtrr_ops[X86_VENDOR_CYRIX]; - size_or_mask = 0xfff00000; /* 32 bits */ + size_or_mask = SIZE_OR_MASK_BITS(32); size_and_mask = 0; } break; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html