Sync up with Linus

.gitignore

@@ -43,6 +43,7 @@ Module.symvers
 /TAGS
 /linux
 /vmlinux
+/vmlinux-gdb.py
 /vmlinuz
 /System.map
 /Module.markers

Documentation/DocBook/device-drivers.tmpl

@@ -190,23 +190,6 @@ X!Edrivers/pnp/system.c
 !Idrivers/message/fusion/mptfc.c
 !Idrivers/message/fusion/mptlan.c
      </sect1>
-     <sect1><title>I2O message devices</title>
-!Iinclude/linux/i2o.h
-!Idrivers/message/i2o/core.h
-!Edrivers/message/i2o/iop.c
-!Idrivers/message/i2o/iop.c
-!Idrivers/message/i2o/config-osm.c
-!Edrivers/message/i2o/exec-osm.c
-!Idrivers/message/i2o/exec-osm.c
-!Idrivers/message/i2o/bus-osm.c
-!Edrivers/message/i2o/device.c
-!Idrivers/message/i2o/device.c
-!Idrivers/message/i2o/driver.c
-!Idrivers/message/i2o/pci.c
-!Idrivers/message/i2o/i2o_block.c
-!Idrivers/message/i2o/i2o_scsi.c
-!Idrivers/message/i2o/i2o_proc.c
-     </sect1>
   </chapter>
 
   <chapter id="snddev">

Documentation/gdb-kernel-debugging.txt

@@ -0,0 +1,160 @@
+Debugging kernel and modules via gdb
+====================================
+
+The kernel debugger kgdb, hypervisors like QEMU or JTAG-based hardware
+interfaces allow to debug the Linux kernel and its modules during runtime
+using gdb. Gdb comes with a powerful scripting interface for python. The
+kernel provides a collection of helper scripts that can simplify typical
+kernel debugging steps. This is a short tutorial about how to enable and use
+them. It focuses on QEMU/KVM virtual machines as target, but the examples can
+be transferred to the other gdb stubs as well.
+
+
+Requirements
+------------
+
+ o gdb 7.2+ (recommended: 7.4+) with python support enabled (typically true
+   for distributions)
+
+
+Setup
+-----
+
+ o Create a virtual Linux machine for QEMU/KVM (see www.linux-kvm.org and
+   www.qemu.org for more details). For cross-development,
+   http://landley.net/aboriginal/bin keeps a pool of machine images and
+   toolchains that can be helpful to start from.
+
+ o Build the kernel with CONFIG_GDB_SCRIPTS enabled, but leave
+   CONFIG_DEBUG_INFO_REDUCED off. If your architecture supports
+   CONFIG_FRAME_POINTER, keep it enabled.
+
+ o Install that kernel on the guest.
+
+   Alternatively, QEMU allows to boot the kernel directly using -kernel,
+   -append, -initrd command line switches. This is generally only useful if
+   you do not depend on modules. See QEMU documentation for more details on
+   this mode.
+
+ o Enable the gdb stub of QEMU/KVM, either
+    - at VM startup time by appending "-s" to the QEMU command line
+   or
+    - during runtime by issuing "gdbserver" from the QEMU monitor
+      console
+
+ o cd /path/to/linux-build
+
+ o Start gdb: gdb vmlinux
+
+   Note: Some distros may restrict auto-loading of gdb scripts to known safe
+   directories. In case gdb reports to refuse loading vmlinux-gdb.py, add
+
+    add-auto-load-safe-path /path/to/linux-build
+
+   to ~/.gdbinit. See gdb help for more details.
+
+ o Attach to the booted guest:
+    (gdb) target remote :1234
+
+
+Examples of using the Linux-provided gdb helpers
+------------------------------------------------
+
+ o Load module (and main kernel) symbols:
+    (gdb) lx-symbols
+    loading vmlinux
+    scanning for modules in /home/user/linux/build
+    loading @0xffffffffa0020000: /home/user/linux/build/net/netfilter/xt_tcpudp.ko
+    loading @0xffffffffa0016000: /home/user/linux/build/net/netfilter/xt_pkttype.ko
+    loading @0xffffffffa0002000: /home/user/linux/build/net/netfilter/xt_limit.ko
+    loading @0xffffffffa00ca000: /home/user/linux/build/net/packet/af_packet.ko
+    loading @0xffffffffa003c000: /home/user/linux/build/fs/fuse/fuse.ko
+    ...
+    loading @0xffffffffa0000000: /home/user/linux/build/drivers/ata/ata_generic.ko
+
+ o Set a breakpoint on some not yet loaded module function, e.g.:
+    (gdb) b btrfs_init_sysfs
+    Function "btrfs_init_sysfs" not defined.
+    Make breakpoint pending on future shared library load? (y or [n]) y
+    Breakpoint 1 (btrfs_init_sysfs) pending.
+
+ o Continue the target
+    (gdb) c
+
+ o Load the module on the target and watch the symbols being loaded as well as
+   the breakpoint hit:
+    loading @0xffffffffa0034000: /home/user/linux/build/lib/libcrc32c.ko
+    loading @0xffffffffa0050000: /home/user/linux/build/lib/lzo/lzo_compress.ko
+    loading @0xffffffffa006e000: /home/user/linux/build/lib/zlib_deflate/zlib_deflate.ko
+    loading @0xffffffffa01b1000: /home/user/linux/build/fs/btrfs/btrfs.ko
+
+    Breakpoint 1, btrfs_init_sysfs () at /home/user/linux/fs/btrfs/sysfs.c:36
+    36              btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
+
+ o Dump the log buffer of the target kernel:
+    (gdb) lx-dmesg
+    [     0.000000] Initializing cgroup subsys cpuset
+    [     0.000000] Initializing cgroup subsys cpu
+    [     0.000000] Linux version 3.8.0-rc4-dbg+ (...
+    [     0.000000] Command line: root=/dev/sda2 resume=/dev/sda1 vga=0x314
+    [     0.000000] e820: BIOS-provided physical RAM map:
+    [     0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
+    [     0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
+    ....
+
+ o Examine fields of the current task struct:
+    (gdb) p $lx_current().pid
+    $1 = 4998
+    (gdb) p $lx_current().comm
+    $2 = "modprobe\000\000\000\000\000\000\000"
+
+ o Make use of the per-cpu function for the current or a specified CPU:
+    (gdb) p $lx_per_cpu("runqueues").nr_running
+    $3 = 1
+    (gdb) p $lx_per_cpu("runqueues", 2).nr_running
+    $4 = 0
+
+ o Dig into hrtimers using the container_of helper:
+    (gdb) set $next = $lx_per_cpu("hrtimer_bases").clock_base[0].active.next
+    (gdb) p *$container_of($next, "struct hrtimer", "node")
+    $5 = {
+      node = {
+        node = {
+          __rb_parent_color = 18446612133355256072,
+          rb_right = 0x0 <irq_stack_union>,
+          rb_left = 0x0 <irq_stack_union>
+        },
+        expires = {
+          tv64 = 1835268000000
+        }
+      },
+      _softexpires = {
+        tv64 = 1835268000000
+      },
+      function = 0xffffffff81078232 <tick_sched_timer>,
+      base = 0xffff88003fd0d6f0,
+      state = 1,
+      start_pid = 0,
+      start_site = 0xffffffff81055c1f <hrtimer_start_range_ns+20>,
+      start_comm = "swapper/2\000\000\000\000\000\000"
+    }
+
+
+List of commands and functions
+------------------------------
+
+The number of commands and convenience functions may evolve over the time,
+this is just a snapshot of the initial version:
+
+ (gdb) apropos lx
+ function lx_current -- Return current task
+ function lx_module -- Find module by name and return the module variable
+ function lx_per_cpu -- Return per-cpu variable
+ function lx_task_by_pid -- Find Linux task by PID and return the task_struct variable
+ function lx_thread_info -- Calculate Linux thread_info from task variable
+ lx-dmesg -- Print Linux kernel log buffer
+ lx-lsmod -- List currently loaded modules
+ lx-symbols -- (Re-)load symbols of Linux kernel and currently loaded modules
+
+Detailed help can be obtained via "help <command-name>" for commands and "help
+function <function-name>" for convenience functions.

MAINTAINERS

@@ -4232,6 +4232,11 @@ W:	http://www.icp-vortex.com/
 S:	Supported
 F:	drivers/scsi/gdt*
 
+GDB KERNEL DEBUGGING HELPER SCRIPTS
+M:	Jan Kiszka <jan.kiszka@siemens.com>
+S:	Supported
+F:	scripts/gdb/
+
 GEMTEK FM RADIO RECEIVER DRIVER
 M:	Hans Verkuil <hverkuil@xs4all.nl>
 L:	linux-media@vger.kernel.org
@@ -6876,7 +6881,7 @@ F:	drivers/scsi/nsp32*
 NIOS2 ARCHITECTURE
 M:	Ley Foon Tan <lftan@altera.com>
 L:	nios2-dev@lists.rocketboards.org (moderated for non-subscribers)
-T:	git git://git.rocketboards.org/linux-socfpga.git
+T:	git git://git.rocketboards.org/linux-socfpga-next.git
 S:	Maintained
 F:	arch/nios2/
 

Makefile

@@ -926,6 +926,9 @@ ifdef CONFIG_SAMPLES
 endif
 ifdef CONFIG_BUILD_DOCSRC
 	$(Q)$(MAKE) $(build)=Documentation
+endif
+ifdef CONFIG_GDB_SCRIPTS
+	$(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
 endif
 	+$(call if_changed,link-vmlinux)
 
@@ -1181,7 +1184,7 @@ MRPROPER_FILES += .config .config.old .version .old_version $(version_h) \
 		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
 		  signing_key.priv signing_key.x509 x509.genkey		\
 		  extra_certificates signing_key.x509.keyid		\
-		  signing_key.x509.signer
+		  signing_key.x509.signer vmlinux-gdb.py
 
 # clean - Delete most, but leave enough to build external modules
 #

arch/nios2/Kconfig

@@ -8,6 +8,7 @@ config NIOS2
 	select GENERIC_IRQ_PROBE
 	select GENERIC_IRQ_SHOW
 	select HAVE_ARCH_TRACEHOOK
+	select HAVE_ARCH_KGDB
 	select IRQ_DOMAIN
 	select MODULES_USE_ELF_RELA
 	select OF
@@ -134,6 +135,14 @@ config NIOS2_PASS_CMDLINE
 	  will override "Default kernel command string".
 	  Say N if you are unsure.
 
+config NIOS2_BOOT_LINK_OFFSET
+	hex "Link address offset for booting"
+	default "0x00500000"
+	help
+	  This option allows you to set the link address offset of the zImage.
+	  This can be useful if you are on a board which has a small amount of
+	  memory.
+
 endmenu
 
 menu "Advanced setup"

arch/nios2/Kconfig.debug

@@ -14,4 +14,15 @@ config DEBUG_STACK_USAGE
 
 	  This option will slow down process creation somewhat.
 
+config EARLY_PRINTK
+	bool "Activate early kernel debugging"
+	default y
+	select SERIAL_CORE_CONSOLE
+	depends on SERIAL_ALTERA_JTAGUART_CONSOLE || SERIAL_ALTERA_UART_CONSOLE
+	help
+	  Enable early printk on console
+	  This is useful for kernel debugging when your machine crashes very
+	  early before the console code is initialized.
+	  You should normally say N here, unless you want to debug such a crash.
+
 endmenu

arch/nios2/boot/Makefile

@@ -24,6 +24,13 @@ $(obj)/vmImage: $(obj)/vmlinux.gz
 	$(call if_changed,uimage)
 	@$(kecho) 'Kernel: $@ is ready'
 
+$(obj)/zImage: $(obj)/compressed/vmlinux FORCE
+	$(call if_changed,objcopy)
+	@$(kecho) 'Kernel: $@ is ready'
+
+$(obj)/compressed/vmlinux: $(obj)/vmlinux.gz FORCE
+	$(Q)$(MAKE) $(build)=$(obj)/compressed $@
+
 # Rule to build device tree blobs
 DTB_SRC := $(patsubst "%",%,$(CONFIG_NIOS2_DTB_SOURCE))
 

arch/nios2/boot/compressed/Makefile

@@ -0,0 +1,19 @@
+#
+# create a compressed vmlinux image from the original vmlinux
+#
+
+targets		:= vmlinux head.o misc.o piggy.o vmlinux.lds
+asflags-y	:=
+
+OBJECTS = $(obj)/head.o $(obj)/misc.o
+
+LDFLAGS_vmlinux := -T
+
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS) $(obj)/piggy.o FORCE
+	$(call if_changed,ld)
+	@:
+
+LDFLAGS_piggy.o := -r --format binary --oformat elf32-littlenios2 -T
+
+$(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/../vmlinux.gz FORCE
+	$(call if_changed,ld)