From 9b6efcd2e2275e13403700913b7a1da92cf11ad2 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 21 Sep 2010 10:54:01 -0600 Subject: [PATCH] lguest: update comments to reflect LHCALL_LOAD_GDT_ENTRY. We used to have a hypercall which reloaded the entire GDT, then we switched to one which loaded a single entry (to match the IDT code). Some comments were not updated, so fix them. Signed-off-by: Rusty Russell Reported by: Eviatar Khen --- arch/x86/lguest/boot.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 9257510b4836..9d5f55848455 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -324,9 +324,8 @@ static void lguest_load_gdt(const struct desc_ptr *desc) } /* - * For a single GDT entry which changes, we do the lazy thing: alter our GDT, - * then tell the Host to reload the entire thing. This operation is so rare - * that this naive implementation is reasonable. + * For a single GDT entry which changes, we simply change our copy and + * then tell the host about it. */ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum, const void *desc, int type) @@ -338,9 +337,13 @@ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum, } /* - * OK, I lied. There are three "thread local storage" GDT entries which change + * There are three "thread local storage" GDT entries which change * on every context switch (these three entries are how glibc implements - * __thread variables). So we have a hypercall specifically for this case. + * __thread variables). As an optimization, we have a hypercall + * specifically for this case. + * + * Wouldn't it be nicer to have a general LOAD_GDT_ENTRIES hypercall + * which took a range of entries? */ static void lguest_load_tls(struct thread_struct *t, unsigned int cpu) { -- 2.20.1