Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

Pull sparc fixes from David Miller:

 1) System call tracing doesn't handle register contents properly across
    the trace.  From Mike Frysinger.

 2) Hook up copy_file_range

 3) Build fix for 32-bit with newer tools.

 4) New sun4v watchdog driver, from Wim Coekaerts.

 5) Set context system call has to allow for servicable faults when we
    flush the register windows to memory

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix sparc64_set_context stack handling.
  sparc32: Add -Wa,-Av8 to KBUILD_CFLAGS.
  Add sun4v_wdt watchdog driver
  sparc: Fix system call tracing register handling.
  sparc: Hook up copy_file_range syscall.

Documentation/watchdog/watchdog-parameters.txt

@@ -400,3 +400,7 @@ wm8350_wdt:
 nowayout: Watchdog cannot be stopped once started
 	(default=kernel config parameter)
 -------------------------------------------------
+sun4v_wdt:
+timeout_ms: Watchdog timeout in milliseconds 1..180000, default=60000)
+nowayout: Watchdog cannot be stopped once started
+-------------------------------------------------

arch/sparc/Makefile

@@ -24,7 +24,13 @@ LDFLAGS        := -m elf32_sparc
 export BITS    := 32
 UTS_MACHINE    := sparc
 
+# We are adding -Wa,-Av8 to KBUILD_CFLAGS to deal with a specs bug in some
+# versions of gcc.  Some gcc versions won't pass -Av8 to binutils when you
+# give -mcpu=v8.  This silently worked with older bintutils versions but
+# does not any more.
 KBUILD_CFLAGS  += -m32 -mcpu=v8 -pipe -mno-fpu -fcall-used-g5 -fcall-used-g7
+KBUILD_CFLAGS  += -Wa,-Av8
+
 KBUILD_AFLAGS  += -m32 -Wa,-Av8
 
 else

arch/sparc/include/uapi/asm/unistd.h

@@ -422,8 +422,9 @@
 #define __NR_listen		354
 #define __NR_setsockopt		355
 #define __NR_mlock2		356
+#define __NR_copy_file_range	357
 
-#define NR_syscalls		357
+#define NR_syscalls		358
 
 /* Bitmask values returned from kern_features system call.  */
 #define KERN_FEATURE_MIXED_MODE_STACK	0x00000001

arch/sparc/kernel/entry.S

@@ -948,7 +948,24 @@ linux_syscall_trace:
 	cmp	%o0, 0
 	bne	3f
 	 mov	-ENOSYS, %o0
+
+	/* Syscall tracing can modify the registers.  */
+	ld	[%sp + STACKFRAME_SZ + PT_G1], %g1
+	sethi	%hi(sys_call_table), %l7
+	ld	[%sp + STACKFRAME_SZ + PT_I0], %i0
+	or	%l7, %lo(sys_call_table), %l7
+	ld	[%sp + STACKFRAME_SZ + PT_I1], %i1
+	ld	[%sp + STACKFRAME_SZ + PT_I2], %i2
+	ld	[%sp + STACKFRAME_SZ + PT_I3], %i3
+	ld	[%sp + STACKFRAME_SZ + PT_I4], %i4
+	ld	[%sp + STACKFRAME_SZ + PT_I5], %i5
+	cmp	%g1, NR_syscalls
+	bgeu	3f
+	 mov	-ENOSYS, %o0
+
+	sll	%g1, 2, %l4
 	mov	%i0, %o0
+	ld	[%l7 + %l4], %l7
 	mov	%i1, %o1
 	mov	%i2, %o2
 	mov	%i3, %o3

arch/sparc/kernel/hvcalls.S

@@ -338,8 +338,9 @@ ENTRY(sun4v_mach_set_watchdog)
 	mov	%o1, %o4
 	mov	HV_FAST_MACH_SET_WATCHDOG, %o5
 	ta	HV_FAST_TRAP
+	brnz,a,pn %o4, 0f
 	stx	%o1, [%o4]
-	retl
+0:	retl
 	 nop
 ENDPROC(sun4v_mach_set_watchdog)
 

arch/sparc/kernel/signal_64.c

@@ -52,7 +52,7 @@ asmlinkage void sparc64_set_context(struct pt_regs *regs)
 	unsigned char fenab;
 	int err;
 
-	flush_user_windows();
+	synchronize_user_stack();
 	if (get_thread_wsaved()					||
 	    (((unsigned long)ucp) & (sizeof(unsigned long)-1))	||
 	    (!__access_ok(ucp, sizeof(*ucp))))

arch/sparc/kernel/sparc_ksyms_64.c

@@ -37,6 +37,7 @@ EXPORT_SYMBOL(sun4v_niagara_getperf);
 EXPORT_SYMBOL(sun4v_niagara_setperf);
 EXPORT_SYMBOL(sun4v_niagara2_getperf);
 EXPORT_SYMBOL(sun4v_niagara2_setperf);
+EXPORT_SYMBOL(sun4v_mach_set_watchdog);
 
 /* from hweight.S */
 EXPORT_SYMBOL(__arch_hweight8);

arch/sparc/kernel/syscalls.S

@@ -158,7 +158,25 @@ linux_syscall_trace32:
 	 add	%sp, PTREGS_OFF, %o0
 	brnz,pn	%o0, 3f
 	 mov	-ENOSYS, %o0
+
+	/* Syscall tracing can modify the registers.  */
+	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
+	sethi	%hi(sys_call_table32), %l7
+	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
+	or	%l7, %lo(sys_call_table32), %l7
+	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
+	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
+	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
+	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
+	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
+
+	cmp	%g1, NR_syscalls
+	bgeu,pn	%xcc, 3f
+	 mov	-ENOSYS, %o0
+
+	sll	%g1, 2, %l4
 	srl	%i0, 0, %o0
+	lduw	[%l7 + %l4], %l7
 	srl	%i4, 0, %o4
 	srl	%i1, 0, %o1
 	srl	%i2, 0, %o2
@@ -170,7 +188,25 @@ linux_syscall_trace:
 	 add	%sp, PTREGS_OFF, %o0
 	brnz,pn	%o0, 3f
 	 mov	-ENOSYS, %o0
+
+	/* Syscall tracing can modify the registers.  */
+	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
+	sethi	%hi(sys_call_table64), %l7
+	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
+	or	%l7, %lo(sys_call_table64), %l7
+	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
+	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
+	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
+	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
+	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
+
+	cmp	%g1, NR_syscalls
+	bgeu,pn	%xcc, 3f
+	 mov	-ENOSYS, %o0
+
+	sll	%g1, 2, %l4
 	mov	%i0, %o0
+	lduw	[%l7 + %l4], %l7
 	mov	%i1, %o1
 	mov	%i2, %o2
 	mov	%i3, %o3

arch/sparc/kernel/systbls_32.S

@@ -88,4 +88,4 @@ sys_call_table:
 /*340*/	.long sys_ni_syscall, sys_kcmp, sys_finit_module, sys_sched_setattr, sys_sched_getattr
 /*345*/	.long sys_renameat2, sys_seccomp, sys_getrandom, sys_memfd_create, sys_bpf
 /*350*/	.long sys_execveat, sys_membarrier, sys_userfaultfd, sys_bind, sys_listen
-/*355*/	.long sys_setsockopt, sys_mlock2
+/*355*/	.long sys_setsockopt, sys_mlock2, sys_copy_file_range

arch/sparc/kernel/systbls_64.S

@@ -89,7 +89,7 @@ sys_call_table32:
 /*340*/	.word sys_kern_features, sys_kcmp, sys_finit_module, sys_sched_setattr, sys_sched_getattr
 	.word sys32_renameat2, sys_seccomp, sys_getrandom, sys_memfd_create, sys_bpf
 /*350*/	.word sys32_execveat, sys_membarrier, sys_userfaultfd, sys_bind, sys_listen
-	.word compat_sys_setsockopt, sys_mlock2
+	.word compat_sys_setsockopt, sys_mlock2, sys_copy_file_range
 
 #endif /* CONFIG_COMPAT */
 
@@ -170,4 +170,4 @@ sys_call_table:
 /*340*/	.word sys_kern_features, sys_kcmp, sys_finit_module, sys_sched_setattr, sys_sched_getattr
 	.word sys_renameat2, sys_seccomp, sys_getrandom, sys_memfd_create, sys_bpf
 /*350*/	.word sys64_execveat, sys_membarrier, sys_userfaultfd, sys_bind, sys_listen
-	.word sys_setsockopt, sys_mlock2
+	.word sys_setsockopt, sys_mlock2, sys_copy_file_range

drivers/watchdog/Kconfig

@@ -1569,6 +1569,17 @@ config WATCHDOG_RIO
 	  machines.  The watchdog timeout period is normally one minute but
 	  can be changed with a boot-time parameter.
 
+config WATCHDOG_SUN4V
+	tristate "Sun4v Watchdog support"
+	select WATCHDOG_CORE
+	depends on SPARC64
+	help
+	  Say Y here to support the hypervisor watchdog capability embedded
+	  in the SPARC sun4v architecture.
+
+	  To compile this driver as a module, choose M here. The module will
+	  be called sun4v_wdt.
+
 # XTENSA Architecture
 
 # Xen Architecture

drivers/watchdog/Makefile

@@ -179,6 +179,7 @@ obj-$(CONFIG_SH_WDT) += shwdt.o
 
 obj-$(CONFIG_WATCHDOG_RIO)		+= riowd.o
 obj-$(CONFIG_WATCHDOG_CP1XXX)		+= cpwd.o
+obj-$(CONFIG_WATCHDOG_SUN4V)		+= sun4v_wdt.o
 
 # XTENSA Architecture
 

drivers/watchdog/sun4v_wdt.c

@@ -0,0 +1,191 @@
+/*
+ *	sun4v watchdog timer
+ *	(c) Copyright 2016 Oracle Corporation
+ *
+ *	Implement a simple watchdog driver using the built-in sun4v hypervisor
+ *	watchdog support. If time expires, the hypervisor stops or bounces
+ *	the guest domain.
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/watchdog.h>
+#include <asm/hypervisor.h>
+#include <asm/mdesc.h>
+
+#define WDT_TIMEOUT			60
+#define WDT_MAX_TIMEOUT			31536000
+#define WDT_MIN_TIMEOUT			1
+#define WDT_DEFAULT_RESOLUTION_MS	1000	/* 1 second */
+
+static unsigned int timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (default="
+	__MODULE_STRING(WDT_TIMEOUT) ")");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, S_IRUGO);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static int sun4v_wdt_stop(struct watchdog_device *wdd)
+{
+	sun4v_mach_set_watchdog(0, NULL);
+
+	return 0;
+}
+
+static int sun4v_wdt_ping(struct watchdog_device *wdd)
+{
+	int hverr;
+
+	/*
+	 * HV watchdog timer will round up the timeout
+	 * passed in to the nearest multiple of the
+	 * watchdog resolution in milliseconds.
+	 */
+	hverr = sun4v_mach_set_watchdog(wdd->timeout * 1000, NULL);
+	if (hverr == HV_EINVAL)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int sun4v_wdt_set_timeout(struct watchdog_device *wdd,
+				 unsigned int timeout)
+{
+	wdd->timeout = timeout;
+
+	return 0;
+}
+
+static const struct watchdog_info sun4v_wdt_ident = {
+	.options =	WDIOF_SETTIMEOUT |
+			WDIOF_MAGICCLOSE |
+			WDIOF_KEEPALIVEPING,
+	.identity =	"sun4v hypervisor watchdog",
+	.firmware_version = 0,
+};
+
+static struct watchdog_ops sun4v_wdt_ops = {
+	.owner =	THIS_MODULE,
+	.start =	sun4v_wdt_ping,
+	.stop =		sun4v_wdt_stop,
+	.ping =		sun4v_wdt_ping,
+	.set_timeout =	sun4v_wdt_set_timeout,
+};
+
+static struct watchdog_device wdd = {
+	.info = &sun4v_wdt_ident,
+	.ops = &sun4v_wdt_ops,
+	.min_timeout = WDT_MIN_TIMEOUT,
+	.max_timeout = WDT_MAX_TIMEOUT,
+	.timeout = WDT_TIMEOUT,
+};
+
+static int __init sun4v_wdt_init(void)
+{
+	struct mdesc_handle *handle;
+	u64 node;
+	const u64 *value;
+	int err = 0;
+	unsigned long major = 1, minor = 1;
+
+	/*
+	 * There are 2 properties that can be set from the control
+	 * domain for the watchdog.
+	 * watchdog-resolution
+	 * watchdog-max-timeout
+	 *
+	 * We can expect a handle to be returned otherwise something
+	 * serious is wrong. Correct to return -ENODEV here.
+	 */
+
+	handle = mdesc_grab();
+	if (!handle)
+		return -ENODEV;
+
+	node = mdesc_node_by_name(handle, MDESC_NODE_NULL, "platform");
+	err = -ENODEV;
+	if (node == MDESC_NODE_NULL)
+		goto out_release;
+
+	/*
+	 * This is a safe way to validate if we are on the right
+	 * platform.
+	 */
+	if (sun4v_hvapi_register(HV_GRP_CORE, major, &minor))
+		goto out_hv_unreg;
+
+	/* Allow value of watchdog-resolution up to 1s (default) */
+	value = mdesc_get_property(handle, node, "watchdog-resolution", NULL);
+	err = -EINVAL;
+	if (value) {
+		if (*value == 0 ||
+		    *value > WDT_DEFAULT_RESOLUTION_MS)
+			goto out_hv_unreg;
+	}
+
+	value = mdesc_get_property(handle, node, "watchdog-max-timeout", NULL);
+	if (value) {
+		/*
+		 * If the property value (in ms) is smaller than
+		 * min_timeout, return -EINVAL.
+		 */
+		if (*value < wdd.min_timeout * 1000)
+			goto out_hv_unreg;
+
+		/*
+		 * If the property value is smaller than
+		 * default max_timeout  then set watchdog max_timeout to
+		 * the value of the property in seconds.
+		 */
+		if (*value < wdd.max_timeout * 1000)
+			wdd.max_timeout = *value  / 1000;
+	}
+
+	watchdog_init_timeout(&wdd, timeout, NULL);
+
+	watchdog_set_nowayout(&wdd, nowayout);
+
+	err = watchdog_register_device(&wdd);
+	if (err)
+		goto out_hv_unreg;
+
+	pr_info("initialized (timeout=%ds, nowayout=%d)\n",
+		 wdd.timeout, nowayout);
+
+	mdesc_release(handle);
+
+	return 0;
+
+out_hv_unreg:
+	sun4v_hvapi_unregister(HV_GRP_CORE);
+
+out_release:
+	mdesc_release(handle);
+	return err;
+}
+
+static void __exit sun4v_wdt_exit(void)
+{
+	sun4v_hvapi_unregister(HV_GRP_CORE);
+	watchdog_unregister_device(&wdd);
+}
+
+module_init(sun4v_wdt_init);
+module_exit(sun4v_wdt_exit);
+
+MODULE_AUTHOR("Wim Coekaerts <wim.coekaerts@oracle.com>");
+MODULE_DESCRIPTION("sun4v watchdog driver");
+MODULE_LICENSE("GPL");