From: Eric W. Biederman Date: Sun, 30 Jul 2006 10:03:20 +0000 (-0700) Subject: [PATCH] machine_kexec.c: Fix the description of segment handling X-Git-Tag: v2.6.18-rc4 X-Git-Url: http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=2a8a3d5b65e86ec1dfef7d268c64a909eab94af7 [PATCH] machine_kexec.c: Fix the description of segment handling One of my original comments in machine_kexec was unclear and this should fix it. Signed-off-by: Eric W. Biederman Cc: Andi Kleen Acked-by: Horms Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- --- a/arch/i386/kernel/machine_kexec.c +++ b/arch/i386/kernel/machine_kexec.c @@ -189,14 +189,11 @@ NORET_TYPE void machine_kexec(struct kim memcpy((void *)reboot_code_buffer, relocate_new_kernel, relocate_new_kernel_size); - /* The segment registers are funny things, they are - * automatically loaded from a table, in memory wherever you - * set them to a specific selector, but this table is never - * accessed again you set the segment to a different selector. - * - * The more common model is are caches where the behide - * the scenes work is done, but is also dropped at arbitrary - * times. + /* The segment registers are funny things, they have both a + * visible and an invisible part. Whenever the visible part is + * set to a specific selector, the invisible part is loaded + * with from a table in memory. At no other time is the + * descriptor table in memory accessed. * * I take advantage of this here by force loading the * segments, before I zap the gdt with an invalid value. --- a/arch/x86_64/kernel/machine_kexec.c +++ b/arch/x86_64/kernel/machine_kexec.c @@ -207,14 +207,11 @@ NORET_TYPE void machine_kexec(struct kim __flush_tlb(); - /* The segment registers are funny things, they are - * automatically loaded from a table, in memory wherever you - * set them to a specific selector, but this table is never - * accessed again unless you set the segment to a different selector. - * - * The more common model are caches where the behide - * the scenes work is done, but is also dropped at arbitrary - * times. + /* The segment registers are funny things, they have both a + * visible and an invisible part. Whenever the visible part is + * set to a specific selector, the invisible part is loaded + * with from a table in memory. At no other time is the + * descriptor table in memory accessed. * * I take advantage of this here by force loading the * segments, before I zap the gdt with an invalid value.