File xsa348-1.patch of Package xen.17645
x86: replace reset_stack_and_jump_nolp()
Move the necessary check into check_for_livepatch_work(), rather than
mostly duplicating reset_stack_and_jump() for this purpose. This is to
prevent an inflation of reset_stack_and_jump() flavors.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -192,7 +192,7 @@ static void noreturn continue_idle_domai
{
/* Idle vcpus might be attached to non-idle units! */
if ( !is_idle_domain(v->sched_unit->domain) )
- reset_stack_and_jump_nolp(guest_idle_loop);
+ reset_stack_and_jump(guest_idle_loop);
reset_stack_and_jump(idle_loop);
}
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -1032,7 +1032,7 @@ static void noreturn svm_do_resume(struc
hvm_do_resume(v);
- reset_stack_and_jump_nolp(svm_asm_do_resume);
+ reset_stack_and_jump(svm_asm_do_resume);
}
void svm_vmenter_helper(const struct cpu_user_regs *regs)
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -1889,7 +1889,7 @@ void vmx_do_resume(struct vcpu *v)
if ( host_cr4 != read_cr4() )
__vmwrite(HOST_CR4, read_cr4());
- reset_stack_and_jump_nolp(vmx_asm_do_vmentry);
+ reset_stack_and_jump(vmx_asm_do_vmentry);
}
static inline unsigned long vmr(unsigned long field)
--- a/xen/arch/x86/pv/domain.c
+++ b/xen/arch/x86/pv/domain.c
@@ -61,7 +61,7 @@ custom_runtime_param("pcid", parse_pcid)
static void noreturn continue_nonidle_domain(struct vcpu *v)
{
check_wakeup_from_wait();
- reset_stack_and_jump_nolp(ret_from_intr);
+ reset_stack_and_jump(ret_from_intr);
}
static int setup_compat_l4(struct vcpu *v)
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -631,7 +631,7 @@ static void __init noreturn reinit_bsp_s
stack_base[0] = stack;
memguard_guard_stack(stack);
- reset_stack_and_jump_nolp(init_done);
+ reset_stack_and_jump(init_done);
}
/*
--- a/xen/common/livepatch.c
+++ b/xen/common/livepatch.c
@@ -1300,6 +1300,11 @@ void check_for_livepatch_work(void)
s_time_t timeout;
unsigned long flags;
+ /* Only do any work when invoked in truly idle state. */
+ if ( system_state != SYS_STATE_active ||
+ !is_idle_domain(current->sched_unit->domain) )
+ return;
+
/* Fast path: no work to do. */
if ( !per_cpu(work_to_do, cpu ) )
return;
--- a/xen/include/asm-x86/current.h
+++ b/xen/include/asm-x86/current.h
@@ -129,22 +129,16 @@ unsigned long get_stack_dump_bottom (uns
# define CHECK_FOR_LIVEPATCH_WORK ""
#endif
-#define switch_stack_and_jump(fn, instr) \
+#define reset_stack_and_jump(fn) \
({ \
__asm__ __volatile__ ( \
"mov %0,%%"__OP"sp;" \
- instr \
+ CHECK_FOR_LIVEPATCH_WORK \
"jmp %c1" \
: : "r" (guest_cpu_user_regs()), "i" (fn) : "memory" ); \
unreachable(); \
})
-#define reset_stack_and_jump(fn) \
- switch_stack_and_jump(fn, CHECK_FOR_LIVEPATCH_WORK)
-
-#define reset_stack_and_jump_nolp(fn) \
- switch_stack_and_jump(fn, "")
-
/*
* Which VCPU's state is currently running on each CPU?
* This is not necesasrily the same as 'current' as a CPU may be