restorer: unmapping native blob in compat task

We need to do it in pure ia32 asm.

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

criu/arch/aarch64/include/asm/types.h

@@ -10,7 +10,6 @@
 #include "bitops.h"
 #include "asm/int.h"
 
-
 typedef void rt_signalfn_t(int, siginfo_t *, void *);
 typedef rt_signalfn_t *rt_sighandler_t;
 
@@ -35,6 +34,8 @@ typedef struct {
 	k_rtsigset_t	rt_sa_mask;
 } rt_sigaction_t;
 
+#define core_is_compat(core)			false
+
 typedef UserAarch64RegsEntry UserRegsEntry;
 
 #define CORE_ENTRY__MARCH CORE_ENTRY__MARCH__AARCH64

criu/arch/arm/include/asm/types.h

@@ -33,6 +33,8 @@ typedef struct {
 	k_rtsigset_t	rt_sa_mask;
 } rt_sigaction_t;
 
+#define core_is_compat(core)			false
+
 typedef UserArmRegsEntry UserRegsEntry;
 
 #define CORE_ENTRY__MARCH CORE_ENTRY__MARCH__ARM

criu/arch/ppc64/include/asm/types.h

@@ -37,11 +37,12 @@ typedef struct {
         k_rtsigset_t rt_sa_mask;               /* mask last for extensibility */
 } rt_sigaction_t;
 
+#define core_is_compat(core)			false
+
 typedef UserPpc64RegsEntry UserRegsEntry;
 
 #define CORE_ENTRY__MARCH	CORE_ENTRY__MARCH__PPC64
 
-
 #define CORE_THREAD_ARCH_INFO(core) core->ti_ppc64
 
 static inline void *decode_pointer(uint64_t v) { return (void*)v; }

criu/cr-restore.c

@@ -105,6 +105,7 @@
 
 #ifndef arch_export_unmap
 #define arch_export_unmap		__export_unmap
+#define arch_export_unmap_compat	__export_unmap_compat
 #endif
 
 struct pstree_item *current;
@@ -2867,7 +2868,12 @@ static int sigreturn_restore(pid_t pid, struct task_restore_args *task_args, uns
 	 */
 	task_args->clone_restore_fn	= restorer_sym(mem, arch_export_restore_thread);
 	restore_task_exec_start		= restorer_sym(mem, arch_export_restore_task);
-	rsti(current)->munmap_restorer	= restorer_sym(mem, arch_export_unmap);
+	if (core_is_compat(core))
+		rsti(current)->munmap_restorer =
+			restorer_sym(mem, arch_export_unmap_compat);
+	else
+		rsti(current)->munmap_restorer =
+			restorer_sym(mem, arch_export_unmap);
 
 	task_args->bootstrap_start = mem;
 	mem += restorer_len;

criu/pie/restorer.c

@@ -885,8 +885,6 @@ static void restore_posix_timers(struct task_restore_args *args)
 		sys_timer_settime((kernel_timer_t)rt->spt.it_id, 0, &rt->val, NULL);
 	}
 }
-static void *bootstrap_start;
-static unsigned int bootstrap_len;
 
 /*
  * sys_munmap must not return here. The control process must
@@ -898,11 +896,34 @@ static unsigned long vdso_rt_size;
 #define vdso_rt_size	(0)
 #endif
 
+static void *bootstrap_start;
+static unsigned int bootstrap_len;
+
 void __export_unmap(void)
 {
 	sys_munmap(bootstrap_start, bootstrap_len - vdso_rt_size);
 }
 
+#ifdef CONFIG_X86_64
+asm (
+	"	.pushsection .text\n"
+	"	.global	__export_unmap_compat\n"
+	"__export_unmap_compat:\n"
+	"	.code32\n"
+	"	mov bootstrap_start, %ebx\n"
+	"	mov bootstrap_len, %ecx\n"
+	"	movl $"__stringify(__NR32_munmap)", %eax\n"
+	"	int	$0x80\n"
+	"	.code64\n"
+	"	.popsection\n"
+);
+extern char __export_unmap_compat;
+#else
+void __export_unmap_compat(void)
+{
+}
+#endif
+
 /*
  * This function unmaps all VMAs, which don't belong to
  * the restored process or the restorer.