Messages in this thread Patch in this message | | | Date | Fri, 15 Aug 2008 17:21:14 +0100 | From | Alex Nixon <> | Subject | [PATCH] change init_gdt to update the gdt via write_gdt, rather than a direct write. |
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From: Alex Nixon <alex.nixon@citrix.com> Date: Fri, 15 Aug 2008 11:21:56 +0100 Subject: [PATCH] change init_gdt to update the gdt via write_gdt, rather than a direct write.
By writing directly, a memory access violation can occur whilst hotplugging a CPU if the entry was previously marked read-only.
Signed-off-by: Alex Nixon <alex.nixon@citrix.com> --- arch/x86/kernel/smpcommon.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/smpcommon.c b/arch/x86/kernel/smpcommon.c index 99941b3..29f8bf0 100644 --- a/arch/x86/kernel/smpcommon.c +++ b/arch/x86/kernel/smpcommon.c @@ -13,13 +13,13 @@ EXPORT_PER_CPU_SYMBOL(this_cpu_off); secondary which will soon come up. */ __cpuinit void init_gdt(int cpu) { - struct desc_struct *gdt = get_cpu_gdt_table(cpu); + struct desc_struct gdt; - pack_descriptor(&gdt[GDT_ENTRY_PERCPU], - __per_cpu_offset[cpu], 0xFFFFF, + pack_descriptor(&gdt, __per_cpu_offset[cpu], 0xFFFFF, 0x2 | DESCTYPE_S, 0x8); + gdt.s = 1; - gdt[GDT_ENTRY_PERCPU].s = 1; + write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PERCPU, &gdt, DESCTYPE_S); per_cpu(this_cpu_off, cpu) = __per_cpu_offset[cpu]; per_cpu(cpu_number, cpu) = cpu; -- 1.5.4.3
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