diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc (renamed from Documentation/ABI/testing/sysfs-class-usb_host) | 4 | ||||
| -rw-r--r-- | Documentation/debugging-via-ohci1394.txt | 8 | ||||
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 38 | ||||
| -rw-r--r-- | Documentation/filesystems/ext3.txt | 16 | ||||
| -rw-r--r-- | Documentation/flexible-arrays.txt | 43 | ||||
| -rw-r--r-- | Documentation/hwmon/sysfs-interface | 57 | ||||
| -rw-r--r-- | Documentation/lguest/lguest.c | 1 | ||||
| -rw-r--r-- | Documentation/sound/alsa/HD-Audio-Models.txt | 1 | ||||
| -rw-r--r-- | Documentation/vm/hwpoison.txt | 136 |
9 files changed, 281 insertions, 23 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-usb_host b/Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc index 46b66ad1f1b..4e8106f7cfd 100644 --- a/Documentation/ABI/testing/sysfs-class-usb_host +++ b/Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc @@ -1,4 +1,4 @@ -What: /sys/class/usb_host/usb_hostN/wusb_chid +What: /sys/class/uwb_rc/uwbN/wusbhc/wusb_chid Date: July 2008 KernelVersion: 2.6.27 Contact: David Vrabel <david.vrabel@csr.com> @@ -9,7 +9,7 @@ Description: Set an all zero CHID to stop the host controller. -What: /sys/class/usb_host/usb_hostN/wusb_trust_timeout +What: /sys/class/uwb_rc/uwbN/wusbhc/wusb_trust_timeout Date: July 2008 KernelVersion: 2.6.27 Contact: David Vrabel <david.vrabel@csr.com> diff --git a/Documentation/debugging-via-ohci1394.txt b/Documentation/debugging-via-ohci1394.txt index 59a91e5c690..611f5a5499b 100644 --- a/Documentation/debugging-via-ohci1394.txt +++ b/Documentation/debugging-via-ohci1394.txt @@ -64,14 +64,14 @@ be used to view the printk buffer of a remote machine, even with live update. Bernhard Kaindl enhanced firescope to support accessing 64-bit machines from 32-bit firescope and vice versa: -- ftp://ftp.suse.de/private/bk/firewire/tools/firescope-0.2.2.tar.bz2 +- http://halobates.de/firewire/firescope-0.2.2.tar.bz2 and he implemented fast system dump (alpha version - read README.txt): -- ftp://ftp.suse.de/private/bk/firewire/tools/firedump-0.1.tar.bz2 +- http://halobates.de/firewire/firedump-0.1.tar.bz2 There is also a gdb proxy for firewire which allows to use gdb to access data which can be referenced from symbols found by gdb in vmlinux: -- ftp://ftp.suse.de/private/bk/firewire/tools/fireproxy-0.33.tar.bz2 +- http://halobates.de/firewire/fireproxy-0.33.tar.bz2 The latest version of this gdb proxy (fireproxy-0.34) can communicate (not yet stable) with kgdb over an memory-based communication module (kgdbom). @@ -178,7 +178,7 @@ Step-by-step instructions for using firescope with early OHCI initialization: Notes ----- -Documentation and specifications: ftp://ftp.suse.de/private/bk/firewire/docs +Documentation and specifications: http://halobates.de/firewire/ FireWire is a trademark of Apple Inc. - for more information please refer to: http://en.wikipedia.org/wiki/FireWire diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 89a47b5aff0..bc693fffabe 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -418,6 +418,14 @@ When: 2.6.33 Why: Should be implemented in userspace, policy daemon. Who: Johannes Berg <johannes@sipsolutions.net> +--------------------------- + +What: CONFIG_INOTIFY +When: 2.6.33 +Why: last user (audit) will be converted to the newer more generic + and more easily maintained fsnotify subsystem +Who: Eric Paris <eparis@redhat.com> + ---------------------------- What: lock_policy_rwsem_* and unlock_policy_rwsem_* will not be @@ -451,3 +459,33 @@ Why: OSS sound_core grabs all legacy minors (0-255) of SOUND_MAJOR will also allow making ALSA OSS emulation independent of sound_core. The dependency will be broken then too. Who: Tejun Heo <tj@kernel.org> + +---------------------------- + +What: Support for VMware's guest paravirtuliazation technique [VMI] will be + dropped. +When: 2.6.37 or earlier. +Why: With the recent innovations in CPU hardware acceleration technologies + from Intel and AMD, VMware ran a few experiments to compare these + techniques to guest paravirtualization technique on VMware's platform. + These hardware assisted virtualization techniques have outperformed the + performance benefits provided by VMI in most of the workloads. VMware + expects that these hardware features will be ubiquitous in a couple of + years, as a result, VMware has started a phased retirement of this + feature from the hypervisor. We will be removing this feature from the + Kernel too. Right now we are targeting 2.6.37 but can retire earlier if + technical reasons (read opportunity to remove major chunk of pvops) + arise. + + Please note that VMI has always been an optimization and non-VMI kernels + still work fine on VMware's platform. + Latest versions of VMware's product which support VMI are, + Workstation 7.0 and VSphere 4.0 on ESX side, future maintainence + releases for these products will continue supporting VMI. + + For more details about VMI retirement take a look at this, + http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html + +Who: Alok N Kataria <akataria@vmware.com> + +---------------------------- diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt index 570f9bd9be2..05d5cf1d743 100644 --- a/Documentation/filesystems/ext3.txt +++ b/Documentation/filesystems/ext3.txt @@ -123,10 +123,18 @@ resuid=n The user ID which may use the reserved blocks. sb=n Use alternate superblock at this location. -quota -noquota -grpquota -usrquota +quota These options are ignored by the filesystem. They +noquota are used only by quota tools to recognize volumes +grpquota where quota should be turned on. See documentation +usrquota in the quota-tools package for more details + (http://sourceforge.net/projects/linuxquota). + +jqfmt=<quota type> These options tell filesystem details about quota +usrjquota=<file> so that quota information can be properly updated +grpjquota=<file> during journal replay. They replace the above + quota options. See documentation in the quota-tools + package for more details + (http://sourceforge.net/projects/linuxquota). bh (*) ext3 associates buffer heads to data pages to nobh (a) cache disk block mapping information diff --git a/Documentation/flexible-arrays.txt b/Documentation/flexible-arrays.txt index 84eb26808de..cb8a3a00cc9 100644 --- a/Documentation/flexible-arrays.txt +++ b/Documentation/flexible-arrays.txt @@ -1,5 +1,5 @@ Using flexible arrays in the kernel -Last updated for 2.6.31 +Last updated for 2.6.32 Jonathan Corbet <corbet@lwn.net> Large contiguous memory allocations can be unreliable in the Linux kernel. @@ -40,6 +40,13 @@ argument is passed directly to the internal memory allocation calls. With the current code, using flags to ask for high memory is likely to lead to notably unpleasant side effects. +It is also possible to define flexible arrays at compile time with: + + DEFINE_FLEX_ARRAY(name, element_size, total); + +This macro will result in a definition of an array with the given name; the +element size and total will be checked for validity at compile time. + Storing data into a flexible array is accomplished with a call to: int flex_array_put(struct flex_array *array, unsigned int element_nr, @@ -76,16 +83,30 @@ particular element has never been allocated. Note that it is possible to get back a valid pointer for an element which has never been stored in the array. Memory for array elements is allocated one page at a time; a single allocation could provide memory for several -adjacent elements. The flexible array code does not know if a specific -element has been written; it only knows if the associated memory is -present. So a flex_array_get() call on an element which was never stored -in the array has the potential to return a pointer to random data. If the -caller does not have a separate way to know which elements were actually -stored, it might be wise, at least, to add GFP_ZERO to the flags argument -to ensure that all elements are zeroed. - -There is no way to remove a single element from the array. It is possible, -though, to remove all elements with a call to: +adjacent elements. Flexible array elements are normally initialized to the +value FLEX_ARRAY_FREE (defined as 0x6c in <linux/poison.h>), so errors +involving that number probably result from use of unstored array entries. +Note that, if array elements are allocated with __GFP_ZERO, they will be +initialized to zero and this poisoning will not happen. + +Individual elements in the array can be cleared with: + + int flex_array_clear(struct flex_array *array, unsigned int element_nr); + +This function will set the given element to FLEX_ARRAY_FREE and return +zero. If storage for the indicated element is not allocated for the array, +flex_array_clear() will return -EINVAL instead. Note that clearing an +element does not release the storage associated with it; to reduce the +allocated size of an array, call: + + int flex_array_shrink(struct flex_array *array); + +The return value will be the number of pages of memory actually freed. +This function works by scanning the array for pages containing nothing but +FLEX_ARRAY_FREE bytes, so (1) it can be expensive, and (2) it will not work +if the array's pages are allocated with __GFP_ZERO. + +It is possible to remove all elements of an array with a call to: void flex_array_free_parts(struct flex_array *array); diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index dcbd502c879..82def883361 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -353,10 +353,20 @@ power[1-*]_average Average power use Unit: microWatt RO -power[1-*]_average_interval Power use averaging interval +power[1-*]_average_interval Power use averaging interval. A poll + notification is sent to this file if the + hardware changes the averaging interval. Unit: milliseconds RW +power[1-*]_average_interval_max Maximum power use averaging interval + Unit: milliseconds + RO + +power[1-*]_average_interval_min Minimum power use averaging interval + Unit: milliseconds + RO + power[1-*]_average_highest Historical average maximum power use Unit: microWatt RO @@ -365,6 +375,18 @@ power[1-*]_average_lowest Historical average minimum power use Unit: microWatt RO +power[1-*]_average_max A poll notification is sent to + power[1-*]_average when power use + rises above this value. + Unit: microWatt + RW + +power[1-*]_average_min A poll notification is sent to + power[1-*]_average when power use + sinks below this value. + Unit: microWatt + RW + power[1-*]_input Instantaneous power use Unit: microWatt RO @@ -381,6 +403,39 @@ power[1-*]_reset_history Reset input_highest, input_lowest, average_highest and average_lowest. WO +power[1-*]_accuracy Accuracy of the power meter. + Unit: Percent + RO + +power[1-*]_alarm 1 if the system is drawing more power than the + cap allows; 0 otherwise. A poll notification is + sent to this file when the power use exceeds the + cap. This file only appears if the cap is known + to be enforced by hardware. + RO + +power[1-*]_cap If power use rises above this limit, the + system should take action to reduce power use. + A poll notification is sent to this file if the + cap is changed by the hardware. The *_cap + files only appear if the cap is known to be + enforced by hardware. + Unit: microWatt + RW + +power[1-*]_cap_hyst Margin of hysteresis built around capping and + notification. + Unit: microWatt + RW + +power[1-*]_cap_max Maximum cap that can be set. + Unit: microWatt + RO + +power[1-*]_cap_min Minimum cap that can be set. + Unit: microWatt + RO + ********** * Energy * ********** diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index ba9373f82ab..098de5bce00 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -42,7 +42,6 @@ #include <signal.h> #include "linux/lguest_launcher.h" #include "linux/virtio_config.h" -#include <linux/virtio_ids.h> #include "linux/virtio_net.h" #include "linux/virtio_blk.h" #include "linux/virtio_console.h" diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 75fddb40f41..4c7f9aee5c4 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -359,6 +359,7 @@ STAC9227/9228/9229/927x 5stack-no-fp D965 5stack without front panel dell-3stack Dell Dimension E520 dell-bios Fixes with Dell BIOS setup + volknob Fixes with volume-knob widget 0x24 auto BIOS setup (default) STAC92HD71B* diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt new file mode 100644 index 00000000000..3ffadf8da61 --- /dev/null +++ b/Documentation/vm/hwpoison.txt @@ -0,0 +1,136 @@ +What is hwpoison? + +Upcoming Intel CPUs have support for recovering from some memory errors +(``MCA recovery''). This requires the OS to declare a page "poisoned", +kill the processes associated with it and avoid using it in the future. + +This patchkit implements the necessary infrastructure in the VM. + +To quote the overview comment: + + * High level machine check handler. Handles pages reported by the + * hardware as being corrupted usually due to a 2bit ECC memory or cache + * failure. + * + * This focusses on pages detected as corrupted in the background. + * When the current CPU tries to consume corruption the currently + * running process can just be killed directly instead. This implies + * that if the error cannot be handled for some reason it's safe to + * just ignore it because no corruption has been consumed yet. Instead + * when that happens another machine check will happen. + * + * Handles page cache pages in various states. The tricky part + * here is that we can access any page asynchronous to other VM + * users, because memory failures could happen anytime and anywhere, + * possibly violating some of their assumptions. This is why this code + * has to be extremely careful. Generally it tries to use normal locking + * rules, as in get the standard locks, even if that means the + * error handling takes potentially a long time. + * + * Some of the operations here are somewhat inefficient and have non + * linear algorithmic complexity, because the data structures have not + * been optimized for this case. This is in particular the case + * for the mapping from a vma to a process. Since this case is expected + * to be rare we hope we can get away with this. + +The code consists of a the high level handler in mm/memory-failure.c, +a new page poison bit and various checks in the VM to handle poisoned +pages. + +The main target right now is KVM guests, but it works for all kinds +of applications. KVM support requires a recent qemu-kvm release. + +For the KVM use there was need for a new signal type so that +KVM can inject the machine check into the guest with the proper +address. This in theory allows other applications to handle +memory failures too. The expection is that near all applications +won't do that, but some very specialized ones might. + +--- + +There are two (actually three) modi memory failure recovery can be in: + +vm.memory_failure_recovery sysctl set to zero: + All memory failures cause a panic. Do not attempt recovery. + (on x86 this can be also affected by the tolerant level of the + MCE subsystem) + +early kill + (can be controlled globally and per process) + Send SIGBUS to the application as soon as the error is detected + This allows applications who can process memory errors in a gentle + way (e.g. drop affected object) + This is the mode used by KVM qemu. + +late kill + Send SIGBUS when the application runs into the corrupted page. + This is best for memory error unaware applications and default + Note some pages are always handled as late kill. + +--- + +User control: + +vm.memory_failure_recovery + See sysctl.txt + +vm.memory_failure_early_kill + Enable early kill mode globally + +PR_MCE_KILL + Set early/late kill mode/revert to system default + arg1: PR_MCE_KILL_CLEAR: Revert to system default + arg1: PR_MCE_KILL_SET: arg2 defines thread specific mode + PR_MCE_KILL_EARLY: Early kill + PR_MCE_KILL_LATE: Late kill + PR_MCE_KILL_DEFAULT: Use system global default +PR_MCE_KILL_GET + return current mode + + +--- + +Testing: + +madvise(MADV_POISON, ....) + (as root) + Poison a page in the process for testing + + +hwpoison-inject module through debugfs + /sys/debug/hwpoison/corrupt-pfn + +Inject hwpoison fault at PFN echoed into this file + + +Architecture specific MCE injector + +x86 has mce-inject, mce-test + +Some portable hwpoison test programs in mce-test, see blow. + +--- + +References: + +http://halobates.de/mce-lc09-2.pdf + Overview presentation from LinuxCon 09 + +git://git.kernel.org/pub/scm/utils/cpu/mce/mce-test.git + Test suite (hwpoison specific portable tests in tsrc) + +git://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git + x86 specific injector + + +--- + +Limitations: + +- Not all page types are supported and never will. Most kernel internal +objects cannot be recovered, only LRU pages for now. +- Right now hugepage support is missing. + +--- +Andi Kleen, Oct 2009 + |