[patch added to 3.12-stable] x86, asmlinkage, lguest: Pass in globals into assembler statement
From: Jiri Slaby <hidden>
Date: 2016-08-18 12:49:57
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Andi Kleen <redacted> This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== commit cdd77e87eae52b7251acc5990207a1c4500a84ce upstream. Tell the compiler that the inline assembler statement references lguest_entry. This fixes compile problems with LTO where the variable and the assembler code may end up in different files. Cc: x86@kernel.org Cc: rusty@rustcorp.com.au Signed-off-by: Andi Kleen <redacted> Signed-off-by: Rusty Russell <redacted> Signed-off-by: Jiri Slaby <redacted> --- drivers/lguest/x86/core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 516923926335..922a1acbf652 100644
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c@@ -157,7 +157,7 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages) * stack, then the address of this call. This stack layout happens to * exactly match the stack layout created by an interrupt... */ - asm volatile("pushf; lcall *lguest_entry" + asm volatile("pushf; lcall *%4" /* * This is how we tell GCC that %eax ("a") and %ebx ("b") * are changed by this routine. The "=" means output.
@@ -169,7 +169,9 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages) * physical address of the Guest's top-level page * directory. */ - : "0"(pages), "1"(__pa(cpu->lg->pgdirs[cpu->cpu_pgd].pgdir)) + : "0"(pages), + "1"(__pa(cpu->lg->pgdirs[cpu->cpu_pgd].pgdir)), + "m"(lguest_entry) /* * We tell gcc that all these registers could change, * which means we don't have to save and restore them in
--
2.9.3