Merge tag 'kvm-x86-selftests_utils-6.10' of https://github.com/kvm-x86/linux into HEAD

KVM selftests treewide updates for 6.10:

 - Define _GNU_SOURCE for all selftests to fix a warning that was introduced by
   a change to kselftest_harness.h late in the 6.9 cycle, and because forcing
   every test to #define _GNU_SOURCE is painful.

 - Provide a global psuedo-RNG instance for all tests, so that library code can
   generate random, but determinstic numbers.

 - Use the global pRNG to randomly force emulation of select writes from guest
   code on x86, e.g. to help validate KVM's emulation of locked accesses.

 - Rename kvm_util_base.h back to kvm_util.h, as the weird layer of indirection
   was added purely to avoid manually #including ucall_common.h in a handful of
   locations.

 - Allocate and initialize x86's GDT, IDT, TSS, segments, and default exception
   handlers at VM creation, instead of forcing tests to manually trigger the
   related setup.

1 files changed, 3 insertions, 10 deletions

diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c
index cf2c73971308..313277486a1d 100644
--- a/tools/testing/selftests/kvm/lib/memstress.c
+++ b/tools/testing/selftests/kvm/lib/memstress.c
@@ -2,14 +2,13 @@
 /*
  * Copyright (C) 2020, Google LLC.
  */
-#define _GNU_SOURCE
-
 #include <inttypes.h>
 #include <linux/bitmap.h>
 
 #include "kvm_util.h"
 #include "memstress.h"
 #include "processor.h"
+#include "ucall_common.h"
 
 struct memstress_args memstress_args;
 
@@ -56,7 +55,7 @@ void memstress_guest_code(uint32_t vcpu_idx)
 	uint64_t page;
 	int i;
 
-	rand_state = new_guest_random_state(args->random_seed + vcpu_idx);
+	rand_state = new_guest_random_state(guest_random_seed + vcpu_idx);
 
 	gva = vcpu_args->gva;
 	pages = vcpu_args->pages;
@@ -76,7 +75,7 @@ void memstress_guest_code(uint32_t vcpu_idx)
 
 			addr = gva + (page * args->guest_page_size);
 
-			if (guest_random_u32(&rand_state) % 100 < args->write_percent)
+			if (__guest_random_bool(&rand_state, args->write_percent))
 				*(uint64_t *)addr = 0x0123456789ABCDEF;
 			else
 				READ_ONCE(*(uint64_t *)addr);
@@ -243,12 +242,6 @@ void memstress_set_write_percent(struct kvm_vm *vm, uint32_t write_percent)
 	sync_global_to_guest(vm, memstress_args.write_percent);
 }
 
-void memstress_set_random_seed(struct kvm_vm *vm, uint32_t random_seed)
-{
-	memstress_args.random_seed = random_seed;
-	sync_global_to_guest(vm, memstress_args.random_seed);
-}
-
 void memstress_set_random_access(struct kvm_vm *vm, bool random_access)
 {
 	memstress_args.random_access = random_access;