diff options
Diffstat (limited to 'pc-bios/bios-pq/0006_kvm-bios-extend-mtrrs-to-above-4g.patch')
| -rw-r--r-- | pc-bios/bios-pq/0006_kvm-bios-extend-mtrrs-to-above-4g.patch | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/pc-bios/bios-pq/0006_kvm-bios-extend-mtrrs-to-above-4g.patch b/pc-bios/bios-pq/0006_kvm-bios-extend-mtrrs-to-above-4g.patch new file mode 100644 index 0000000000..7350b47992 --- /dev/null +++ b/pc-bios/bios-pq/0006_kvm-bios-extend-mtrrs-to-above-4g.patch @@ -0,0 +1,62 @@ +extend MTRRs to above 4G (Alex Williamson) + +When I try to boot guests using a recent Linux kernel (2.6.26+), memory +above 3.5G gets thrown away with an error like this: + +WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing 4608MB of RAM + +This extends MTRRs to cover all of memory. + +Signed-off-by: Alex Williamson <alex.williamson@hp.com> +Signed-off-by: Avi Kivity <avi@redhat.com> +Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> + +Index: bochs/bios/rombios32.c +=================================================================== +--- bochs.orig/bios/rombios32.c ++++ bochs/bios/rombios32.c +@@ -427,6 +427,7 @@ uint32_t cpuid_signature; + uint32_t cpuid_features; + uint32_t cpuid_ext_features; + unsigned long ram_size; ++uint64_t above4g_ram_size; + uint8_t bios_uuid[16]; + #ifdef BX_USE_EBDA_TABLES + unsigned long ebda_cur_addr; +@@ -561,6 +562,14 @@ void setup_mtrr(void) + wrmsr_smp(MTRRphysMask_MSR(i), (~vmask & 0xfffffff000ull) | 0x800); + vbase += vmask + 1; + } ++ for (vbase = 1ull << 32; i < vcnt && vbase < above4g_ram_size; ++i) { ++ vmask = (1ull << 40) - 1; ++ while (vbase + vmask + 1 > above4g_ram_size) ++ vmask >>= 1; ++ wrmsr_smp(MTRRphysBase_MSR(i), vbase | 6); ++ wrmsr_smp(MTRRphysMask_MSR(i), (~vmask & 0xfffffff000ull) | 0x800); ++ vbase += vmask + 1; ++ } + wrmsr_smp(MSR_MTRRdefType, 0xc00); + } + +@@ -572,11 +581,19 @@ void ram_probe(void) + else + ram_size = (cmos_readb(0x30) | (cmos_readb(0x31) << 8)) * 1024 + + 1 * 1024 * 1024; ++ if (cmos_readb(0x5b) | cmos_readb(0x5c) | cmos_readb(0x5d)) ++ above4g_ram_size = ((uint64_t)cmos_readb(0x5b) << 16) | ++ ((uint64_t)cmos_readb(0x5c) << 24) | ((uint64_t)cmos_readb(0x5d) << 32); ++ ++ if (above4g_ram_size) ++ above4g_ram_size += 1ull << 32; ++ + BX_INFO("ram_size=0x%08lx\n", ram_size); + #ifdef BX_USE_EBDA_TABLES + ebda_cur_addr = ((*(uint16_t *)(0x40e)) << 4) + 0x380; + BX_INFO("ebda_cur_addr: 0x%08lx\n", ebda_cur_addr); + #endif ++ BX_INFO("top of ram %ldMB\n", above4g_ram_size >> 20); + setup_mtrr(); + } + + + |