Merge commit 'refs/top-bases/fix-branch' into fix-branch

lib/libzpool/include/sys/zfs_context.h

@@ -211,6 +211,12 @@ _NOTE(CONSTCOND) } while (0)
 #define	STACK_SIZE		24576	/* Solaris */
 #endif
 
+#ifdef NPTL_GUARD_WITHIN_STACK
+#define	EXTRA_GUARD_BYTES	PAGESIZE
+#else
+#define	EXTRA_GUARD_BYTES	0
+#endif
+
 /* in libzpool, p0 exists only to have its address taken */
 typedef struct proc {
 	uintptr_t	this_is_never_used_dont_dereference_it;

lib/libzpool/kernel.c

@@ -162,8 +162,16 @@ zk_thread_create(caddr_t stk, size_t stksize, thread_func_t func, void *arg,
 	 * kernel space.  PTHREAD_STACK_MIN is the minimum stack
 	 * required for a NULL procedure in user space and is added
 	 * in to the stack requirements.
+	 *
+	 * Some buggy NPTL threading implementations include the
+	 * guard area within the stack size allocations.  In
+	 * this case we allocate an extra page to account for the
+	 * guard area since we only have two pages of usable stack
+	 * on Linux.
 	 */
-	stack = PTHREAD_STACK_MIN + MAX(stksize, STACK_SIZE);
+
+	stack = PTHREAD_STACK_MIN + MAX(stksize, STACK_SIZE) +
+			EXTRA_GUARD_BYTES;
 
 	VERIFY3S(pthread_attr_init(&attr), ==, 0);
 	VERIFY3S(pthread_attr_setstacksize(&attr, stack), ==, 0);