From f6de7a39c181dfb8a2c534661a53c73afb3081cd Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Wed, 4 Sep 2013 10:08:54 -0400 Subject: NFSv4: Document the recover_lost_locks kernel parameter Rename the new 'recover_locks' kernel parameter to 'recover_lost_locks' and change the default to 'false'. Document why in Documentation/kernel-parameters.txt Move the 'recover_lost_locks' kernel parameter to fs/nfs/super.c to make it easy to backport to kernels prior to 3.6.x, which don't have a separate NFSv4 module. Signed-off-by: Trond Myklebust --- Documentation/kernel-parameters.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 15356aca938c..30584b194984 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1847,6 +1847,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted. will be sent. The default is to send the implementation identification information. + + nfs.recover_lost_locks = + [NFSv4] Attempt to recover locks that were lost due + to a lease timeout on the server. Please note that + doing this risks data corruption, since there are + no guarantees that the file will remain unchanged + after the locks are lost. + If you want to enable the kernel legacy behaviour of + attempting to recover these locks, then set this + parameter to '1'. + The default parameter value of '0' causes the kernel + not to attempt recovery of lost locks. nfsd.nfs4_disable_idmapping= [NFSv4] When set to the default of '1', the NFSv4 -- cgit v1.2.1 From 15a3eac0784edb73cb2ec0f0c97705ba4bd39b3f Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Wed, 25 Sep 2013 10:07:20 -0400 Subject: xen/spinlock: Document the xen_nopvspin parameter. Which disables in the ticketlock slowpath the Xen PV optimization's. Useful for diagnosing issues and comparing benchmarks in over-commit CPU scenarios. Signed-off-by: Konrad Rzeszutek Wilk --- Documentation/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7f9d4f53882c..b9589127b3ee 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -3412,6 +3412,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. the unplug protocol never -- do not unplug even if version check succeeds + xen_nopvspin [X86,XEN] + Disables the ticketlock slowpath using Xen PV + optimizations. + xirc2ps_cs= [NET,PCMCIA] Format: ,,,,,[,[,[,]]] -- cgit v1.2.1 From 675217fd9950a668a33f9ee3fac3df34fd5113d0 Mon Sep 17 00:00:00 2001 From: Weiping Pan Date: Mon, 30 Sep 2013 13:45:10 -0700 Subject: Documentation/kernel-parameters.txt: replace kernelcore with Movable Han Pingtian found a typo in Documentation/kernel-parameters.txt about "kernelcore=", that "kernelcore" should be replaced with "Movable" here. Signed-off-by: Weiping Pan Acked-by: Mel Gorman Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 539a23631990..73d23fdc512b 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1357,7 +1357,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. pages. In the event, a node is too small to have both kernelcore and Movable pages, kernelcore pages will take priority and other nodes will have a larger number - of kernelcore pages. The Movable zone is used for the + of Movable pages. The Movable zone is used for the allocation of pages that may be reclaimed or moved by the page migration subsystem. This means that HugeTLB pages may not be allocated from this zone. -- cgit v1.2.1 From 080506ad0aa9c9fbc7879cdd290d55624da08c60 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Mon, 30 Sep 2013 13:45:19 -0700 Subject: block: change config option name for cmdline partition parsing Recently commit bab55417b10c ("block: support embedded device command line partition") introduced CONFIG_CMDLINE_PARSER. However, that name is too generic and sounds like it enables/disables generic kernel boot arg processing, when it really is block specific. Before this option becomes a part of a full/final release, add the BLK_ prefix to it so that it is clear in absence of any other context that it is block specific. In addition, fix up the following less critical items: - help text was not really at all helpful. - index file for Documentation was not updated - add the new arg to Documentation/kernel-parameters.txt - clarify wording in source comments Signed-off-by: Paul Gortmaker Cc: Jens Axboe Cc: Cai Zhiyong Cc: Wei Yongjun Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 73d23fdc512b..fcbb736d55fe 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -480,6 +480,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: ,, See header of drivers/net/hamradio/baycom_ser_hdx.c. + blkdevparts= Manual partition parsing of block device(s) for + embedded devices based on command line input. + See Documentation/block/cmdline-partition.txt + boot_delay= Milliseconds to delay each printk during boot. Values larger than 10 seconds (10000) are changed to no delay (0). -- cgit v1.2.1 From 4102adab9189c8ea2f0cdd2f88345fd25d2790f1 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 8 Oct 2013 20:23:47 -0700 Subject: rcu: Move RCU-related source code to kernel/rcu directory Signed-off-by: Paul E. McKenney Reviewed-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 95 ++++++++++++++++++++++--------------- 1 file changed, 57 insertions(+), 38 deletions(-) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 1a036cd972fb..c3dc13e90a40 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2595,7 +2595,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. ramdisk_size= [RAM] Sizes of RAM disks in kilobytes See Documentation/blockdev/ramdisk.txt. - rcu_nocbs= [KNL,BOOT] + rcu_nocbs= [KNL] In kernels built with CONFIG_RCU_NOCB_CPU=y, set the specified list of CPUs to be no-callback CPUs. Invocation of these CPUs' RCU callbacks will @@ -2608,7 +2608,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. real-time workloads. It can also improve energy efficiency for asymmetric multiprocessors. - rcu_nocb_poll [KNL,BOOT] + rcu_nocb_poll [KNL] Rather than requiring that offloaded CPUs (specified by rcu_nocbs= above) explicitly awaken the corresponding "rcuoN" kthreads, @@ -2619,126 +2619,145 @@ bytes respectively. Such letter suffixes can also be entirely omitted. energy efficiency by requiring that the kthreads periodically wake up to do the polling. - rcutree.blimit= [KNL,BOOT] + rcutree.blimit= [KNL] Set maximum number of finished RCU callbacks to process in one batch. - rcutree.fanout_leaf= [KNL,BOOT] + rcutree.rcu_fanout_leaf= [KNL] Increase the number of CPUs assigned to each leaf rcu_node structure. Useful for very large systems. - rcutree.jiffies_till_first_fqs= [KNL,BOOT] + rcutree.jiffies_till_first_fqs= [KNL] Set delay from grace-period initialization to first attempt to force quiescent states. Units are jiffies, minimum value is zero, and maximum value is HZ. - rcutree.jiffies_till_next_fqs= [KNL,BOOT] + rcutree.jiffies_till_next_fqs= [KNL] Set delay between subsequent attempts to force quiescent states. Units are jiffies, minimum value is one, and maximum value is HZ. - rcutree.qhimark= [KNL,BOOT] + rcutree.qhimark= [KNL] Set threshold of queued RCU callbacks over which batch limiting is disabled. - rcutree.qlowmark= [KNL,BOOT] + rcutree.qlowmark= [KNL] Set threshold of queued RCU callbacks below which batch limiting is re-enabled. - rcutree.rcu_cpu_stall_suppress= [KNL,BOOT] - Suppress RCU CPU stall warning messages. - - rcutree.rcu_cpu_stall_timeout= [KNL,BOOT] - Set timeout for RCU CPU stall warning messages. - - rcutree.rcu_idle_gp_delay= [KNL,BOOT] + rcutree.rcu_idle_gp_delay= [KNL] Set wakeup interval for idle CPUs that have RCU callbacks (RCU_FAST_NO_HZ=y). - rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT] + rcutree.rcu_idle_lazy_gp_delay= [KNL] Set wakeup interval for idle CPUs that have only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y). Lazy RCU callbacks are those which RCU can prove do nothing more than free memory. - rcutorture.fqs_duration= [KNL,BOOT] + rcutorture.fqs_duration= [KNL] Set duration of force_quiescent_state bursts. - rcutorture.fqs_holdoff= [KNL,BOOT] + rcutorture.fqs_holdoff= [KNL] Set holdoff time within force_quiescent_state bursts. - rcutorture.fqs_stutter= [KNL,BOOT] + rcutorture.fqs_stutter= [KNL] Set wait time between force_quiescent_state bursts. - rcutorture.irqreader= [KNL,BOOT] - Test RCU readers from irq handlers. + rcutorture.gp_exp= [KNL] + Use expedited update-side primitives. + + rcutorture.gp_normal= [KNL] + Use normal (non-expedited) update-side primitives. + If both gp_exp and gp_normal are set, do both. + If neither gp_exp nor gp_normal are set, still + do both. - rcutorture.n_barrier_cbs= [KNL,BOOT] + rcutorture.n_barrier_cbs= [KNL] Set callbacks/threads for rcu_barrier() testing. - rcutorture.nfakewriters= [KNL,BOOT] + rcutorture.nfakewriters= [KNL] Set number of concurrent RCU writers. These just stress RCU, they don't participate in the actual test, hence the "fake". - rcutorture.nreaders= [KNL,BOOT] + rcutorture.nreaders= [KNL] Set number of RCU readers. - rcutorture.onoff_holdoff= [KNL,BOOT] + rcutorture.object_debug= [KNL] + Enable debug-object double-call_rcu() testing. + + rcutorture.onoff_holdoff= [KNL] Set time (s) after boot for CPU-hotplug testing. - rcutorture.onoff_interval= [KNL,BOOT] + rcutorture.onoff_interval= [KNL] Set time (s) between CPU-hotplug operations, or zero to disable CPU-hotplug testing. - rcutorture.shuffle_interval= [KNL,BOOT] + rcutorture.rcutorture_runnable= [BOOT] + Start rcutorture running at boot time. + + rcutorture.shuffle_interval= [KNL] Set task-shuffle interval (s). Shuffling tasks allows some CPUs to go into dyntick-idle mode during the rcutorture test. - rcutorture.shutdown_secs= [KNL,BOOT] + rcutorture.shutdown_secs= [KNL] Set time (s) after boot system shutdown. This is useful for hands-off automated testing. - rcutorture.stall_cpu= [KNL,BOOT] + rcutorture.stall_cpu= [KNL] Duration of CPU stall (s) to test RCU CPU stall warnings, zero to disable. - rcutorture.stall_cpu_holdoff= [KNL,BOOT] + rcutorture.stall_cpu_holdoff= [KNL] Time to wait (s) after boot before inducing stall. - rcutorture.stat_interval= [KNL,BOOT] + rcutorture.stat_interval= [KNL] Time (s) between statistics printk()s. - rcutorture.stutter= [KNL,BOOT] + rcutorture.stutter= [KNL] Time (s) to stutter testing, for example, specifying five seconds causes the test to run for five seconds, wait for five seconds, and so on. This tests RCU's ability to transition abruptly to and from idle. - rcutorture.test_boost= [KNL,BOOT] + rcutorture.test_boost= [KNL] Test RCU priority boosting? 0=no, 1=maybe, 2=yes. "Maybe" means test if the RCU implementation under test support RCU priority boosting. - rcutorture.test_boost_duration= [KNL,BOOT] + rcutorture.test_boost_duration= [KNL] Duration (s) of each individual boost test. - rcutorture.test_boost_interval= [KNL,BOOT] + rcutorture.test_boost_interval= [KNL] Interval (s) between each boost test. - rcutorture.test_no_idle_hz= [KNL,BOOT] + rcutorture.test_no_idle_hz= [KNL] Test RCU's dyntick-idle handling. See also the rcutorture.shuffle_interval parameter. - rcutorture.torture_type= [KNL,BOOT] + rcutorture.torture_type= [KNL] Specify the RCU implementation to test. - rcutorture.verbose= [KNL,BOOT] + rcutorture.verbose= [KNL] Enable additional printk() statements. + rcupdate.rcu_expedited= [KNL] + Use expedited grace-period primitives, for + example, synchronize_rcu_expedited() instead + of synchronize_rcu(). This reduces latency, + but can increase CPU utilization, degrade + real-time latency, and degrade energy efficiency. + + rcupdate.rcu_cpu_stall_suppress= [KNL] + Suppress RCU CPU stall warning messages. + + rcupdate.rcu_cpu_stall_timeout= [KNL] + Set timeout for RCU CPU stall warning messages. + rdinit= [KNL] Format: Run specified binary instead of /init from the ramdisk, -- cgit v1.2.1 From 712b6aa8731a7e148298c58cea66a5209c659e3c Mon Sep 17 00:00:00 2001 From: Kuppuswamy Sathyanarayanan Date: Thu, 17 Oct 2013 15:35:29 -0700 Subject: intel_mid: Renamed *mrst* to *intel_mid* mrst is used as common name to represent all intel_mid type soc's. But moorsetwon is just one of the intel_mid soc. So renamed them to use intel_mid. This patch mainly renames the variables and related functions that uses *mrst* prefix with *intel_mid*. To ensure that there are no functional changes, I have compared the objdump of related files before and after rename and found the only difference is symbol and name changes. Signed-off-by: Kuppuswamy Sathyanarayanan Link: http://lkml.kernel.org/r/1382049336-21316-6-git-send-email-david.a.cohen@linux.intel.com Signed-off-by: David Cohen Signed-off-by: H. Peter Anvin --- Documentation/kernel-parameters.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index fcbb736d55fe..dfaeb0c65f88 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -3471,11 +3471,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. default x2apic cluster mode on platforms supporting x2apic. - x86_mrst_timer= [X86-32,APBT] - Choose timer option for x86 Moorestown MID platform. + x86_intel_mid_timer= [X86-32,APBT] + Choose timer option for x86 Intel MID platform. Two valid options are apbt timer only and lapic timer plus one apbt timer for broadcast timer. - x86_mrst_timer=apbt_only | lapic_and_apbt + x86_intel_mid_timer=apbt_only | lapic_and_apbt xen_emul_unplug= [HW,X86,XEN] Unplug Xen emulated devices -- cgit v1.2.1 From 9b9d4ce592d283fc4c01da746c02a840c499bb7e Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Fri, 7 Jun 2013 12:16:35 +0200 Subject: ima: define kernel parameter 'ima_template=' to change configured default This patch allows users to specify from the kernel command line the template descriptor, among those defined, that will be used to generate and display measurement entries. If an user specifies a wrong template, IMA reverts to the template descriptor set in the kernel configuration. Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar --- Documentation/kernel-parameters.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 1a036cd972fb..2b78cb55ac34 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1190,6 +1190,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. programs exec'd, files mmap'd for exec, and all files opened for read by uid=0. + ima_template= [IMA] + Select one of defined IMA measurements template formats. + Formats: { "ima" | "ima-ng" } + Default: "ima-ng" + init= [KNL] Format: Run specified binary instead of /sbin/init as init -- cgit v1.2.1 From e7a2ad7eb6f48ad80c70a22dd8167fb34b409466 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Fri, 7 Jun 2013 12:16:37 +0200 Subject: ima: enable support for larger default filedata hash algorithms The IMA measurement list contains two hashes - a template data hash and a filedata hash. The template data hash is committed to the TPM, which is limited, by the TPM v1.2 specification, to 20 bytes. The filedata hash is defined as 20 bytes as well. Now that support for variable length measurement list templates was added, the filedata hash is not limited to 20 bytes. This patch adds Kconfig support for defining larger default filedata hash algorithms and replacing the builtin default with one specified on the kernel command line. contains a list of hash algorithms. The Kconfig default hash algorithm is a subset of this list, but any hash algorithm included in the list can be specified at boot, using the 'ima_hash=' kernel command line option. Changelog v2: - update Kconfig Changelog: - support hashes that are configured - use generic HASH_ALGO_ definitions - add Kconfig support - hash_setup must be called only once (Dmitry) - removed trailing whitespaces (Roberto Sassu) Signed-off-by: Mimi Zohar Signed-off-by: Roberto Sassu --- Documentation/kernel-parameters.txt | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 2b78cb55ac34..1e8761c89a2c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1181,9 +1181,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. owned by uid=0. ima_hash= [IMA] - Format: { "sha1" | "md5" } + Format: { md5 | sha1 | rmd160 | sha256 | sha384 + | sha512 | ... } default: "sha1" + The list of supported hash algorithms is defined + in crypto/hash_info.h. + ima_tcb [IMA] Load a policy which meets the needs of the Trusted Computing Base. This means IMA will measure all -- cgit v1.2.1 From 72548e836b0c4abbb652e791dee9c91203a9a4c6 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 4 Oct 2013 09:36:56 +0100 Subject: x86/efi: Add EFI framebuffer earlyprintk support It's incredibly difficult to diagnose early EFI boot issues without special hardware because earlyprintk=vga doesn't work on EFI systems. Add support for writing to the EFI framebuffer, via earlyprintk=efi, which will actually give users a chance of providing debug output. Cc: H. Peter Anvin Acked-by: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Jones Signed-off-by: Matt Fleming --- Documentation/kernel-parameters.txt | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7f9d4f53882c..7a0f202d482e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -792,6 +792,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. earlyprintk= [X86,SH,BLACKFIN,ARM] earlyprintk=vga + earlyprintk=efi earlyprintk=xen earlyprintk=serial[,ttySn[,baudrate]] earlyprintk=serial[,0x...[,baudrate]] @@ -805,7 +806,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Append ",keep" to not disable it when the real console takes over. - Only vga or serial or usb debug port at a time. + Only one of vga, efi, serial, or usb debug port can + be used at a time. Currently only ttyS0 and ttyS1 may be specified by name. Other I/O ports may be explicitly specified @@ -819,8 +821,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Interaction with the standard serial driver is not very good. - The VGA output is eventually overwritten by the real - console. + The VGA and EFI output is eventually overwritten by + the real console. The xen output can only be used by Xen PV guests. -- cgit v1.2.1 From c5320926e370b4cfb8f10c2169e26f960079cf67 Mon Sep 17 00:00:00 2001 From: Tang Chen Date: Tue, 12 Nov 2013 15:08:10 -0800 Subject: mem-hotplug: introduce movable_node boot option The hot-Pluggable field in SRAT specifies which memory is hotpluggable. As we mentioned before, if hotpluggable memory is used by the kernel, it cannot be hot-removed. So memory hotplug users may want to set all hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it. Memory hotplug users may also set a node as movable node, which has ZONE_MOVABLE only, so that the whole node can be hot-removed. But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the kernel cannot use memory in movable nodes. This will cause NUMA performance down. And other users may be unhappy. So we need a way to allow users to enable and disable this functionality. In this patch, we introduce movable_node boot option to allow users to choose to not to consume hotpluggable memory at early boot time and later we can set it as ZONE_MOVABLE. To achieve this, the movable_node boot option will control the memblock allocation direction. That said, after memblock is ready, before SRAT is parsed, we should allocate memory near the kernel image as we explained in the previous patches. So if movable_node boot option is set, the kernel does the following: 1. After memblock is ready, make memblock allocate memory bottom up. 2. After SRAT is parsed, make memblock behave as default, allocate memory top down. Users can specify "movable_node" in kernel commandline to enable this functionality. For those who don't use memory hotplug or who don't want to lose their NUMA performance, just don't specify anything. The kernel will work as before. Signed-off-by: Tang Chen Signed-off-by: Zhang Yanfei Suggested-by: Kamezawa Hiroyuki Suggested-by: Ingo Molnar Acked-by: Tejun Heo Acked-by: Toshi Kani Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Wanpeng Li Cc: Thomas Renninger Cc: Yinghai Lu Cc: Jiang Liu Cc: Wen Congyang Cc: Lai Jiangshan Cc: Yasuaki Ishimatsu Cc: Taku Izumi Cc: Mel Gorman Cc: Michal Nazarewicz Cc: Minchan Kim Cc: Rik van Riel Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index fd3ecedc084d..882a40d405c8 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1775,6 +1775,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. that the amount of memory usable for all allocations is not too small. + movable_node [KNL,X86] Boot-time switch to enable the effects + of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details. + MTD_Partition= [MTD] Format: ,,, -- cgit v1.2.1 From 3d035f580699feba352f8703cced127fc203f0dd Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Tue, 12 Nov 2013 15:08:33 -0800 Subject: drivers/char/hpet.c: allow user controlled mmap for user processes The CONFIG_HPET_MMAP Kconfig option exposes the memory map of the HPET registers to userspace. The Kconfig help points out that in some cases this can be a security risk as some systems may erroneously configure the map such that additional data is exposed to userspace. This is a problem for distributions -- some users want the MMAP functionality but it comes with a significant security risk. In an effort to mitigate this risk, and due to the low number of users of the MMAP functionality, I've introduced a kernel parameter, hpet_mmap_enable, that is required in order to actually have the HPET MMAP exposed. Signed-off-by: Prarit Bhargava Acked-by: Matt Wilson Signed-off-by: Clemens Ladisch Cc: Randy Dunlap Cc: Tomas Winkler Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/kernel-parameters.txt') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 882a40d405c8..9ca3e74a10e1 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1070,6 +1070,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. VIA, nVidia) verbose: show contents of HPET registers during setup + hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET + registers. Default set by CONFIG_HPET_MMAP_DEFAULT. + hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot. hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages. On x86-64 and powerpc, this option can be specified -- cgit v1.2.1