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x86: add LongModeAddressSize function to cpuid

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LongModeAddressSize was used by kernel 2.6.28.4 for physical address
validation, if not properly implemented, PCI resource allocation may
failed because of ioremap failed:

- linux-2.6.28.4/arch/x86/mm/ioremap.c:27-30
  27 static inline int phys_addr_valid(unsigned long addr)
  28 {
  29     return addr < (1UL << boot_cpu_data.x86_phys_bits);
  30 }

- linux-2.6.28.4/arch/x86/kernel/cpu/common.c:475-482
 475 #ifdef CONFIG_X86_64
 476         if (c->extended_cpuid_level >= 0x80000008) {
 477                 u32 eax = cpuid_eax(0x80000008);
 478
 479                 c->x86_virt_bits = (eax >> 8) & 0xff;
 480                 c->x86_phys_bits = eax & 0xff;
 481         }
 482 #endif

- linux-2.6.28.4/arch/x86/mm/ioremap.c:209-214
 209 if (!phys_addr_valid(phys_addr)) {
 210     printk(KERN_WARNING "ioremap: invalid physical address %llx\n",
 211            (unsigned long long)phys_addr);
 212     WARN_ON_ONCE(1);
 213     return NULL;
 214 }

This patch return 0x0000ffff for LongModeAddressSize, which guarantee phys_addr_valid never failed.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
This commit is contained in:
Jiuyue Ma 2014-06-13 16:48:47 +08:00
parent e1a5522a89
commit 9fb8b8515b
1 changed files with 7 additions and 4 deletions
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11
src/arch/x86/cpuid.cc
View file

@ -48,12 +48,12 @@ namespace X86ISA {
L1CacheAndTLB,
L2L3CacheAndL2TLB,
APMInfo,
LongModeAddressSize,
/*
* The following are defined by the spec but not yet implemented
*/
/* LongModeAddressSize,
// Function 9 is reserved
/* // Function 9 is reserved
SVMInfo = 10,
// Functions 11-24 are reserved
TLB1GBPageInfo = 25,
@ -130,8 +130,11 @@ namespace X86ISA {
result = CpuidResult(0x80000018, 0x68747541,
0x69746e65, 0x444d4163);
break;
/* case LongModeAddressSize:
case SVMInfo:
case LongModeAddressSize:
result = CpuidResult(0x0000ffff, 0x00000000,
0x00000000, 0x00000000);
break;
/* case SVMInfo:
case TLB1GBPageInfo:
case PerformanceInfo:*/
default: