From f616fe4feee4000c2995d2d1e1981513bf9ab0d4 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 8 May 2013 10:06:55 +0930 Subject: lguest: clear cached last cpu when guest_set_pgd() called. commit v3.9-rc1-53-g6d0cda9 "lguest: cache last cpu we ran on." missed one case, which causes a triple fault. The guest calls guest_set_pgd() on the top page, and we carefully remap the Switcher text page. But we didn't reset last_host_cpu, so map_switcher_in_guest() thinks the guest's regs and IDT/GDT etc are already mapped. Reported-by: Paul Bolle Tested-by: Paul Bolle Signed-off-by: Rusty Russell --- drivers/lguest/page_tables.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c index 699187ab3800..5b9ac32801c7 100644 --- a/drivers/lguest/page_tables.c +++ b/drivers/lguest/page_tables.c @@ -1002,6 +1002,7 @@ void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 idx) kill_guest(&lg->cpus[0], "Cannot populate switcher mapping"); } + lg->pgdirs[pgdir].last_host_cpu = -1; } } -- cgit v1.2.2