---

yaml
---
r: 40076
b: refs/heads/master
c: 7c2aed4
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 43518407d57f1b685f5a9f1a981734ce66a21f76
+refs/heads/master: 7c2aed4b5632fb536721b8494d1a4a65852ffb49

trunk/Documentation/HOWTO

@@ -395,6 +395,26 @@ bugme-janitor mailing list (every change in the bugzilla is mailed here)
 
 
 
+Managing bug reports
+--------------------
+
+One of the best ways to put into practice your hacking skills is by fixing
+bugs reported by other people. Not only you will help to make the kernel
+more stable, you'll learn to fix real world problems and you will improve
+your skills, and other developers will be aware of your presence. Fixing
+bugs is one of the best ways to get merits among other developers, because
+not many people like wasting time fixing other people's bugs.
+
+To work in the already reported bug reports, go to http://bugzilla.kernel.org.
+If you want to be advised of the future bug reports, you can subscribe to the
+bugme-new mailing list (only new bug reports are mailed here) or to the
+bugme-janitor mailing list (every change in the bugzilla is mailed here)
+
+	http://lists.osdl.org/mailman/listinfo/bugme-new
+	http://lists.osdl.org/mailman/listinfo/bugme-janitors
+
+
+
 Mailing lists
 -------------
 

trunk/Documentation/MSI-HOWTO.txt

@@ -470,7 +470,68 @@ LOC:     324553     325068
 ERR:          0
 MIS:          0
 
-6. FAQ
+6. MSI quirks
+
+Several PCI chipsets or devices are known to not support MSI.
+The PCI stack provides 3 possible levels of MSI disabling:
+* on a single device
+* on all devices behind a specific bridge
+* globally
+
+6.1. Disabling MSI on a single device
+
+Under some circumstances, it might be required to disable MSI on a
+single device, It may be achived by either not calling pci_enable_msi()
+or all, or setting the pci_dev->no_msi flag before (most of the time
+in a quirk).
+
+6.2. Disabling MSI below a bridge
+
+The vast majority of MSI quirks are required by PCI bridges not
+being able to route MSI between busses. In this case, MSI have to be
+disabled on all devices behind this bridge. It is achieves by setting
+the PCI_BUS_FLAGS_NO_MSI flag in the pci_bus->bus_flags of the bridge
+subordinate bus. There is no need to set the same flag on bridges that
+are below the broken brigde. When pci_enable_msi() is called to enable
+MSI on a device, pci_msi_supported() takes care of checking the NO_MSI
+flag in all parent busses of the device.
+
+Some bridges actually support dynamic MSI support enabling/disabling
+by changing some bits in their PCI configuration space (especially
+the Hypertransport chipsets such as the nVidia nForce and Serverworks
+HT2000). It may then be required to update the NO_MSI flag on the
+corresponding devices in the sysfs hierarchy. To enable MSI support
+on device "0000:00:0e", do:
+
+	echo 1 > /sys/bus/pci/devices/0000:00:0e/msi_bus
+
+To disable MSI support, echo 0 instead of 1. Note that it should be
+used with caution since changing this value might break interrupts.
+
+6.3. Disabling MSI globally
+
+Some extreme cases may require to disable MSI globally on the system.
+For now, the only known case is a Serverworks PCI-X chipsets (MSI are
+not supported on several busses that are not all connected to the
+chipset in the Linux PCI hierarchy). In the vast majority of other
+cases, disabling only behind a specific bridge is enough.
+
+For debugging purpose, the user may also pass pci=nomsi on the kernel
+command-line to explicitly disable MSI globally. But, once the appro-
+priate quirks are added to the kernel, this option should not be
+required anymore.
+
+6.4. Finding why MSI cannot be enabled on a device
+
+Assuming that MSI are not enabled on a device, you should look at
+dmesg to find messages that quirks may output when disabling MSI
+on some devices, some bridges or even globally.
+Then, lspci -t gives the list of bridges above a device. Reading
+/sys/bus/pci/devices/0000:00:0e/msi_bus will tell you whether MSI
+are enabled (1) or disabled (0). In 0 is found in a single bridge
+msi_bus file above the device, MSI cannot be enabled.
+
+7. FAQ
 
 Q1. Are there any limitations on using the MSI?
 

trunk/Documentation/cpu-hotplug.txt

@@ -46,7 +46,7 @@ maxcpus=n    Restrict boot time cpus to n. Say if you have 4 cpus, using
              maxcpus=2 will only boot 2. You can choose to bring the
              other cpus later online, read FAQ's for more info.
 
-additional_cpus*=n	Use this to limit hotpluggable cpus. This option sets
+additional_cpus=n (*)	Use this to limit hotpluggable cpus. This option sets
   			cpu_possible_map = cpu_present_map + additional_cpus
 
 (*) Option valid only for following architectures
@@ -101,15 +101,15 @@ cpu_possible_map/for_each_possible_cpu() to iterate.
 
 Never use anything other than cpumask_t to represent bitmap of CPUs.
 
-#include <linux/cpumask.h>
+	#include <linux/cpumask.h>
 
-for_each_possible_cpu     - Iterate over cpu_possible_map
-for_each_online_cpu       - Iterate over cpu_online_map
-for_each_present_cpu      - Iterate over cpu_present_map
-for_each_cpu_mask(x,mask) - Iterate over some random collection of cpu mask.
+	for_each_possible_cpu     - Iterate over cpu_possible_map
+	for_each_online_cpu       - Iterate over cpu_online_map
+	for_each_present_cpu      - Iterate over cpu_present_map
+	for_each_cpu_mask(x,mask) - Iterate over some random collection of cpu mask.
 
-#include <linux/cpu.h>
-lock_cpu_hotplug() and unlock_cpu_hotplug():
+	#include <linux/cpu.h>
+	lock_cpu_hotplug() and unlock_cpu_hotplug():
 
 The above calls are used to inhibit cpu hotplug operations. While holding the
 cpucontrol mutex, cpu_online_map will not change. If you merely need to avoid
@@ -120,7 +120,7 @@ will work as long as stop_machine_run() is used to take a cpu down.
 
 CPU Hotplug - Frequently Asked Questions.
 
-Q: How to i enable my kernel to support CPU hotplug?
+Q: How to enable my kernel to support CPU hotplug?
 A: When doing make defconfig, Enable CPU hotplug support
 
    "Processor type and Features" -> Support for Hotpluggable CPUs
@@ -141,57 +141,57 @@ A: You should now notice an entry in sysfs.
 Check if sysfs is mounted, using the "mount" command. You should notice
 an entry as shown below in the output.
 
-....
-none on /sys type sysfs (rw)
-....
+	....
+	none on /sys type sysfs (rw)
+	....
 
-if this is not mounted, do the following.
+If this is not mounted, do the following.
 
-#mkdir /sysfs
-#mount -t sysfs sys /sys
+	 #mkdir /sysfs
+	#mount -t sysfs sys /sys
 
-now you should see entries for all present cpu, the following is an example
+Now you should see entries for all present cpu, the following is an example
 in a 8-way system.
 
-#pwd
-#/sys/devices/system/cpu
-#ls -l
-total 0
-drwxr-xr-x  10 root root 0 Sep 19 07:44 .
-drwxr-xr-x  13 root root 0 Sep 19 07:45 ..
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu0
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu1
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu2
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu3
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu4
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu5
-drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu6
-drwxr-xr-x   3 root root 0 Sep 19 07:48 cpu7
+	#pwd
+	#/sys/devices/system/cpu
+	#ls -l
+	total 0
+	drwxr-xr-x  10 root root 0 Sep 19 07:44 .
+	drwxr-xr-x  13 root root 0 Sep 19 07:45 ..
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu0
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu1
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu2
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu3
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu4
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu5
+	drwxr-xr-x   3 root root 0 Sep 19 07:44 cpu6
+	drwxr-xr-x   3 root root 0 Sep 19 07:48 cpu7
 
 Under each directory you would find an "online" file which is the control
 file to logically online/offline a processor.
 
 Q: Does hot-add/hot-remove refer to physical add/remove of cpus?
 A: The usage of hot-add/remove may not be very consistently used in the code.
-CONFIG_CPU_HOTPLUG enables logical online/offline capability in the kernel.
+CONFIG_HOTPLUG_CPU enables logical online/offline capability in the kernel.
 To support physical addition/removal, one would need some BIOS hooks and
 the platform should have something like an attention button in PCI hotplug.
 CONFIG_ACPI_HOTPLUG_CPU enables ACPI support for physical add/remove of CPUs.
 
 Q: How do i logically offline a CPU?
 A: Do the following.
 
-#echo 0 > /sys/devices/system/cpu/cpuX/online
+	#echo 0 > /sys/devices/system/cpu/cpuX/online
 
-once the logical offline is successful, check
+Once the logical offline is successful, check
 
-#cat /proc/interrupts
+	#cat /proc/interrupts
 
-you should now not see the CPU that you removed. Also online file will report
+You should now not see the CPU that you removed. Also online file will report
 the state as 0 when a cpu if offline and 1 when its online.
 
-#To display the current cpu state.
-#cat /sys/devices/system/cpu/cpuX/online
+	#To display the current cpu state.
+	#cat /sys/devices/system/cpu/cpuX/online
 
 Q: Why cant i remove CPU0 on some systems?
 A: Some architectures may have some special dependency on a certain CPU.
@@ -234,8 +234,8 @@ Q: If i have some kernel code that needs to be aware of CPU arrival and
    departure, how to i arrange for proper notification?
 A: This is what you would need in your kernel code to receive notifications.
 
-    #include <linux/cpu.h>
-    static int __cpuinit foobar_cpu_callback(struct notifier_block *nfb,
+	#include <linux/cpu.h>
+	static int __cpuinit foobar_cpu_callback(struct notifier_block *nfb,
 					    unsigned long action, void *hcpu)
 	{
 		unsigned int cpu = (unsigned long)hcpu;
@@ -279,10 +279,10 @@ Q: I don't see my action being called for all CPUs already up and running?
 A: Yes, CPU notifiers are called only when new CPUs are on-lined or offlined.
    If you need to perform some action for each cpu already in the system, then
 
-  for_each_online_cpu(i) {
+	for_each_online_cpu(i) {
 		foobar_cpu_callback(&foobar_cpu_notifier, CPU_UP_PREPARE, i);
-		foobar_cpu_callback(&foobar-cpu_notifier, CPU_ONLINE, i);
-  }
+		foobar_cpu_callback(&foobar_cpu_notifier, CPU_ONLINE, i);
+	}
 
 Q: If i would like to develop cpu hotplug support for a new architecture,
    what do i need at a minimum?
@@ -307,38 +307,38 @@ Q: I need to ensure that a particular cpu is not removed when there is some
    work specific to this cpu is in progress.
 A: First switch the current thread context to preferred cpu
 
-   int my_func_on_cpu(int cpu)
-   {
-       cpumask_t saved_mask, new_mask = CPU_MASK_NONE;
-       int curr_cpu, err = 0;
-
-       saved_mask = current->cpus_allowed;
-       cpu_set(cpu, new_mask);
-       err = set_cpus_allowed(current, new_mask);
-
-       if (err)
-           return err;
-
-       /*
-        * If we got scheduled out just after the return from
-        * set_cpus_allowed() before running the work, this ensures
-        * we stay locked.
-        */
-       curr_cpu = get_cpu();
-
-       if (curr_cpu != cpu) {
-	   err = -EAGAIN;
-           goto ret;
-       } else {
-       	   /*
-	    * Do work : But cant sleep, since get_cpu() disables preempt
-	    */
-       }
-    ret:
-    	put_cpu();
-	set_cpus_allowed(current, saved_mask);
-	return err;
-    }
+	int my_func_on_cpu(int cpu)
+	{
+		cpumask_t saved_mask, new_mask = CPU_MASK_NONE;
+		int curr_cpu, err = 0;
+
+		saved_mask = current->cpus_allowed;
+		cpu_set(cpu, new_mask);
+		err = set_cpus_allowed(current, new_mask);
+
+		if (err)
+			return err;
+
+		/*
+		 * If we got scheduled out just after the return from
+		 * set_cpus_allowed() before running the work, this ensures
+		 * we stay locked.
+		 */
+		curr_cpu = get_cpu();
+
+		if (curr_cpu != cpu) {
+			err = -EAGAIN;
+			goto ret;
+		} else {
+			/*
+			 * Do work : But cant sleep, since get_cpu() disables preempt
+			 */
+		}
+		ret:
+			put_cpu();
+			set_cpus_allowed(current, saved_mask);
+			return err;
+		}
 
 
 Q: How do we determine how many CPUs are available for hotplug.

trunk/Documentation/feature-removal-schedule.txt

@@ -255,7 +255,7 @@ Who:	Stephen Hemminger <shemminger@osdl.org>
 
 
 What:	PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
-When:	Oktober 2008
+When:	October 2008
 Why:	The stacking of class devices makes these values misleading and
 	inconsistent.
 	Class devices should not carry any of these properties, and bus

trunk/Documentation/filesystems/00-INDEX

@@ -34,6 +34,8 @@ ext2.txt
 	- info, mount options and specifications for the Ext2 filesystem.
 ext3.txt
 	- info, mount options and specifications for the Ext3 filesystem.
+ext4.txt
+	- info, mount options and specifications for the Ext4 filesystem.
 files.txt
 	- info on file management in the Linux kernel.
 fuse.txt