summaryrefslogtreecommitdiff
path: root/Documentation/kernel-parameters.txt
AgeCommit message (Collapse)Author
2018-03-19x86/paravirt: Remove 'noreplace-paravirt' cmdline optionJosh Poimboeuf
commit 12c69f1e94c89d40696e83804dd2f0965b5250cd upstream. The 'noreplace-paravirt' option disables paravirt patching, leaving the original pv indirect calls in place. That's highly incompatible with retpolines, unless we want to uglify paravirt even further and convert the paravirt calls to retpolines. As far as I can tell, the option doesn't seem to be useful for much other than introducing surprising corner cases and making the kernel vulnerable to Spectre v2. It was probably a debug option from the early paravirt days. So just remove it. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Dan Williams <dan.j.williams@intel.com> Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-03-19x86/spectre: Add boot time option to select Spectre v2 mitigationDavid Woodhouse
commit da285121560e769cc31797bba6422eea71d473e0 upstream. Add a spectre_v2= option to select the mitigation used for the indirect branch speculation vulnerability. Currently, the only option available is retpoline, in its various forms. This will be expanded to cover the new IBRS/IBPB microcode features. The RETPOLINE_AMD feature relies on a serializing LFENCE for speculation control. For AMD hardware, only set RETPOLINE_AMD if LFENCE is a serializing instruction, which is indicated by the LFENCE_RDTSC feature. [ tglx: Folded back the LFENCE/AMD fixes and reworked it so IBRS integration becomes simple ] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-5-git-send-email-dwmw@amazon.co.uk [bwh: Backported to 3.16: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-03-19x86/Documentation: Add PTI descriptionDave Hansen
commit 01c9b17bf673b05bb401b76ec763e9730ccf1376 upstream. Add some details about how PTI works, what some of the downsides are, and how to debug it when things go wrong. Also document the kernel parameter: 'pti/nopti'. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at> Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at> Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at> Cc: Richard Fellner <richard.fellner@student.tugraz.at> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Andi Lutomirsky <luto@kernel.org> Link: https://lkml.kernel.org/r/20180105174436.1BC6FA2B@viggo.jf.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09x86/kaiser: Check boottime cmdline paramsBorislav Petkov
AMD (and possibly other vendors) are not affected by the leak KAISER is protecting against. Keep the "nopti" for traditional reasons and add pti=<on|off|auto> like upstream. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09x86/kaiser: Rename and simplify X86_FEATURE_KAISER handlingBorislav Petkov
Concentrate it in arch/x86/mm/kaiser.c and use the upstream string "nopti". Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09kaiser: add "nokaiser" boot option, using ALTERNATIVEHugh Dickins
Added "nokaiser" boot option: an early param like "noinvpcid". Most places now check int kaiser_enabled (#defined 0 when not CONFIG_KAISER) instead of #ifdef CONFIG_KAISER; but entry_64.S and entry_64_compat.S are using the ALTERNATIVE technique, which patches in the preferred instructions at runtime. That technique is tied to x86 cpu features, so X86_FEATURE_KAISER fabricated ("" in its comment so "kaiser" not magicked into /proc/cpuinfo). Prior to "nokaiser", Kaiser #defined _PAGE_GLOBAL 0: revert that, but be careful with both _PAGE_GLOBAL and CR4.PGE: setting them when nokaiser like when !CONFIG_KAISER, but not setting either when kaiser - neither matters on its own, but it's hard to be sure that _PAGE_GLOBAL won't get set in some obscure corner, or something add PGE into CR4. By omitting _PAGE_GLOBAL from __supported_pte_mask when kaiser_enabled, all page table setup which uses pte_pfn() masks it out of the ptes. It's slightly shameful that the same declaration versus definition of kaiser_enabled appears in not one, not two, but in three header files (asm/kaiser.h, asm/pgtable.h, asm/tlbflush.h). I felt safer that way, than with #including any of those in any of the others; and did not feel it worth an asm/kaiser_enabled.h - kernel/cpu/common.c includes them all, so we shall hear about it if they get out of synch. Cleanups while in the area: removed the silly #ifdef CONFIG_KAISER from kaiser.c; removed the unused native_get_normal_pgd(); removed the spurious reg clutter from SWITCH_*_CR3 macro stubs; corrected some comments. But more interestingly, set CR4.PSE in secondary_startup_64: the manual is clear that it does not matter whether it's 0 or 1 when 4-level-pts are enabled, but I was distracted to find cr4 different on BSP and auxiliaries - BSP alone was adding PSE, in probe_page_size_mask(). (cherry picked from Change-Id: I8e5bec716944444359cbd19f6729311eff943e9a) Signed-off-by: Hugh Dickins <hughd@google.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09x86/mm: Add the 'nopcid' boot option to turn off PCIDAndy Lutomirski
commit 0790c9aad84901ca1bdc14746175549c8b5da215 upstream. The parameter is only present on x86_64 systems to save a few bytes, as PCID is always disabled on x86_32. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/8bbb2e65bcd249a5f18bfb8128b4689f08ac2b60.1498751203.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> [Hugh Dickins: Backported to 3.18: - Documentation/admin-guide/kernel-parameters.txt (not in this tree) - Documentation/kernel-parameters.txt (patched instead of that) Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09x86/mm: Add a 'noinvpcid' boot option to turn off INVPCIDAndy Lutomirski
commit d12a72b844a49d4162f24cefdab30bed3f86730e upstream. This adds a chicken bit to turn off INVPCID in case something goes wrong. It's an early_param() because we do TLB flushes before we parse __setup() parameters. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/f586317ed1bc2b87aee652267e515b90051af385.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-07-02mm: larger stack guard gap, between vmasHugh Dickins
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream. Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Original-patch-by: Oleg Nesterov <oleg@redhat.com> Original-patch-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [Hugh Dickins: Backported to 3.16] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-06-05x86/platform/goldfish: Prevent unconditional loadingThomas Gleixner
commit 47512cfd0d7a8bd6ab71d01cd89fca19eb2093eb upstream. The goldfish platform code registers the platform device unconditionally which causes havoc in several ways if the goldfish_pdev_bus driver is enabled: - Access to the hardcoded physical memory region, which is either not available or contains stuff which is completely unrelated. - Prevents that the interrupt of the serial port can be requested - In case of a spurious interrupt it goes into a infinite loop in the interrupt handler of the pdev_bus driver (which needs to be fixed seperately). Add a 'goldfish' command line option to make the registration opt-in when the platform is compiled in. I'm seriously grumpy about this engineering trainwreck, which has seven SOBs from Intel developers for 50 lines of code. And none of them figured out that this is broken. Impressive fail! Fixes: ddd70cf93d78 ("goldfish: platform device for x86") Reported-by: Gabriel C <nix.or.die@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-06-15USB: uas: Add a new NO_REPORT_LUNS quirkHans de Goede
commit 1363074667a6b7d0507527742ccd7bbed5e3ceaa upstream. Add a new NO_REPORT_LUNS quirk and set it for Seagate drives with an usb-id of: 0bc2:331a, as these will fail to respond to a REPORT_LUNS command. Reported-and-tested-by: David Webb <djw@noc.ac.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2015-05-12uas: Add US_FL_MAX_SECTORS_240 flagHans de Goede
commit ee136af4a064c2f61e2025873584d2c7ec93f4ae upstream. The usb-storage driver sets max_sectors = 240 in its scsi-host template, for uas we do not want to do that for all devices, but testing has shown that some devices need it. This commit adds a US_FL_MAX_SECTORS_240 flag for such devices, and implements support for it in uas.c, while at it it also adds support for US_FL_MAX_SECTORS_64 to uas.c. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2015-02-04Input: i8042 - reset keyboard to fix Elantech touchpad detectionSrihari Vijayaraghavan
commit 148e9a711e034e06310a8c36b64957934ebe30f2 upstream. On some laptops, keyboard needs to be reset in order to successfully detect touchpad (e.g., some Gigabyte laptop models with Elantech touchpads). Without resettin keyboard touchpad pretends to be completely dead. Based on the original patch by Mateusz Jończyk this version has been expanded to include DMI based detection & application of the fix automatically on the affected models of laptops. This has been confirmed to fix problem by three users already on three different models of laptops. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=81331 Signed-off-by: Srihari Vijayaraghavan <linux.bug.reporting@gmail.com> Acked-by: Mateusz Jończyk <mat.jonczyk@o2.pl> Tested-by: Srihari Vijayaraghavan <linux.bug.reporting@gmail.com> Tested by: Zakariya Dehlawi <zdehlawi@gmail.com> Tested-by: Guillaum Bouchard <guillaum.bouchard@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-10-15uas: Add no-report-opcodes quirkHans de Goede
commit 734016b00b50a3c6a0e1fc1b7b217e783f5123a1 upstream. Besides the ASM1051 (*) needing sdev->no_report_opcodes = 1, it turns out that the JMicron JMS567 also needs it to work properly with uas (usb-storage always sets it). Since some of the scsi devs were not to keen on the idea to outrightly set sdev->no_report_opcodes = 1 for all uas devices, so add a quirk for this, and set it for the JMS567. *) Which has become a non-issue since we've completely blacklisted uas on the ASM1051 for other reasons Reported-and-tested-by: Claudio Bizzarri <claudio.bizzarri@gmail.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-15uas: Add a quirk for rejecting ATA_12 and ATA_16 commandsHans de Goede
commit 593078525c8b234a35a36ff551b8716464e86481 upstream. And set this quirk for the Seagate Expansion Desk (0bc2:2312), as that one seems to hang upon receiving an ATA_12 or ATA_16 command. https://bugzilla.kernel.org/show_bug.cgi?id=79511 https://bbs.archlinux.org/viewtopic.php?id=183190 While at it also add missing documentation for the u value for usb-storage quirks. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-05USB: document the 'u' flag for usb-storage quirks parameterAlan Stern
commit b6089f19fe0cec625b5963a851a07c3e412c27c8 upstream. Commit d24d481b7d36 (usb-storage: Modify and export adjust_quirks so that it can be used by uas) added the 'u' flag to the quirks module parameter for usb-storage, but neglected to update the documentation. This patch adds the documentation. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-19Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fixes from Thomas Gleixner: "Two RCU patches: - Address a serious performance regression on open/close caused by commit ac1bea85781e ("Make cond_resched() report RCU quiescent states") - Export RCU debug functions. Not a regression, but enablement to address a serious recursion bug in the sl*b allocators in 3.17" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Reduce overhead of cond_resched() checks for RCU rcu: Export debug_init_rcu_head() and and debug_init_rcu_head()
2014-07-14Revert "ACPI / video: change acpi-video brightness_switch_enabled default to 0"Rafael J. Wysocki
This reverts commit 886129a8eebeb (ACPI / video: change acpi-video brightness_switch_enabled default to 0) as it is reported to cause problems to happen. Fixes: 886129a8eebeb (ACPI / video: change acpi-video brightness_switch_enabled default to 0) Link: http://marc.info/?l=linux-acpi&m=140534286826819&w=2 Reported by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-25Merge branch 'urgent.2014.06.23a' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent Pull RCU fixes from Paul E. McKenney: " This series includes the following: 1. Export a pair of debug-object interfaces for RCU that will allow the slab allocators to avoid a recursion bug located by Sasha Levin. Strictly speaking, this is not a regression, but it would be good to enable the fix. 2. Address a serious performance regression on an open/close micro-benchmark located by Dave Hansen. The offending commit is ac1bea85781e (Make cond_resched() report RCU quiescent states). " Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-23kernel/watchdog.c: print traces for all cpus on lockup detectionAaron Tomlin
A 'softlockup' is defined as a bug that causes the kernel to loop in kernel mode for more than a predefined period to time, without giving other tasks a chance to run. Currently, upon detection of this condition by the per-cpu watchdog task, debug information (including a stack trace) is sent to the system log. On some occasions, we have observed that the "victim" rather than the actual "culprit" (i.e. the owner/holder of the contended resource) is reported to the user. Often this information has proven to be insufficient to assist debugging efforts. To avoid loss of useful debug information, for architectures which support NMI, this patch makes it possible to improve soft lockup reporting. This is accomplished by issuing an NMI to each cpu to obtain a stack trace. If NMI is not supported we just revert back to the old method. A sysctl and boot-time parameter is available to toggle this feature. [dzickus@redhat.com: add CONFIG_SMP in certain areas] [akpm@linux-foundation.org: additional CONFIG_SMP=n optimisations] [mq@suse.cz: fix warning] Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Don Zickus <dzickus@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jan Moskyto Matejka <mq@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-23rcu: Reduce overhead of cond_resched() checks for RCUPaul E. McKenney
Commit ac1bea85781e (Make cond_resched() report RCU quiescent states) fixed a problem where a CPU looping in the kernel with but one runnable task would give RCU CPU stall warnings, even if the in-kernel loop contained cond_resched() calls. Unfortunately, in so doing, it introduced performance regressions in Anton Blanchard's will-it-scale "open1" test. The problem appears to be not so much the increased cond_resched() path length as an increase in the rate at which grace periods complete, which increased per-update grace-period overhead. This commit takes a different approach to fixing this bug, mainly by moving the RCU-visible quiescent state from cond_resched() to rcu_note_context_switch(), and by further reducing the check to a simple non-zero test of a single per-CPU variable. However, this approach requires that the force-quiescent-state processing send resched IPIs to the offending CPUs. These will be sent only once the grace period has reached an age specified by the boot/sysfs parameter rcutree.jiffies_till_sched_qs, or once the grace period reaches an age halfway to the point at which RCU CPU stall warnings will be emitted, whichever comes first. Reported-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@gentwo.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> [ paulmck: Made rcu_momentary_dyntick_idle() as suggested by the ktest build robot. Also fixed smp_mb() comment as noted by Oleg Nesterov. ] Merge with e552592e (Reduce overhead of cond_resched() checks for RCU) Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-06-16x86, kaslr: boot-time selectable with hibernationKees Cook
Changes kASLR from being compile-time selectable (blocked by CONFIG_HIBERNATION), to being boot-time selectable (with hibernation available by default) via the "kaslr" kernel command line. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-16PM / hibernate: introduce "nohibernate" boot parameterKees Cook
To support using kernel features that are not compatible with hibernation, this creates the "nohibernate" kernel boot parameter to disable both hibernation and resume. This allows hibernation support to be a boot-time choice instead of only a compile-time choice. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-11Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Most of this is cleaning up various driver sysfs permissions so we can re-add the perm check (we unified the module param and sysfs checks, but the module ones were stronger so we weakened them temporarily). Param parsing gets documented, and also "--" now forces args to be handed to init (and ignored by the kernel). Module NX/RO protections get tightened: we now set them before calling parse_args()" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: module: set nx before marking module MODULE_STATE_COMING. samples/kobject/: avoid world-writable sysfs files. drivers/hid/hid-picolcd_fb: avoid world-writable sysfs files. drivers/staging/speakup/: avoid world-writable sysfs files. drivers/regulator/virtual: avoid world-writable sysfs files. drivers/scsi/pm8001/pm8001_ctl.c: avoid world-writable sysfs files. drivers/hid/hid-lg4ff.c: avoid world-writable sysfs files. drivers/video/fbdev/sm501fb.c: avoid world-writable sysfs files. drivers/mtd/devices/docg3.c: avoid world-writable sysfs files. speakup: fix incorrect perms on speakup_acntsa.c cpumask.h: silence warning with -Wsign-compare Documentation: Update kernel-parameters.tx param: hand arguments after -- straight to init modpost: Fix resource leak in read_dump()
2014-06-06kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump after ↵Masami Hiramatsu
panic_notifers Add a "crash_kexec_post_notifiers" boot option to run kdump after running panic_notifiers and dump kmsg. This can help rare situations where kdump fails because of unstable crashed kernel or hardware failure (memory corruption on critical data/code), or the 2nd kernel is already broken by the 1st kernel (it's a broken behavior, but who can guarantee that the "crashed" kernel works correctly?). Usage: add "crash_kexec_post_notifiers" to kernel boot option. Note that this actually increases risks of the failure of kdump. This option should be set only if you worry about the rare case of kdump failure rather than increasing the chance of success. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Motohiro Kosaki <Motohiro.Kosaki@us.fujitsu.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Cc: Satoru MORIYA <satoru.moriya.br@hitachi.com> Cc: Tomoki Sekiyama <tomoki.sekiyama@hds.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04init/main.c: add initcall_blacklist kernel parameterPrarit Bhargava
When a module is built into the kernel the module_init() function becomes an initcall. Sometimes debugging through dynamic debug can help, however, debugging built in kernel modules is typically done by changing the .config, recompiling, and booting the new kernel in an effort to determine exactly which module caused a problem. This patchset can be useful stand-alone or combined with initcall_debug. There are cases where some initcalls can hang the machine before the console can be flushed, which can make initcall_debug output inaccurate. Having the ability to skip initcalls can help further debugging of these scenarios. Usage: initcall_blacklist=<list of comma separated initcalls> ex) added "initcall_blacklist=sgi_uv_sysfs_init" as a kernel parameter and the log contains: blacklisting initcall sgi_uv_sysfs_init ... ... initcall sgi_uv_sysfs_init blacklisted ex) added "initcall_blacklist=foo_bar,sgi_uv_sysfs_init" as a kernel parameter and the log contains: blacklisting initcall foo_bar blacklisting initcall sgi_uv_sysfs_init ... ... initcall sgi_uv_sysfs_init blacklisted [akpm@linux-foundation.org: tweak printk text] Signed-off-by: Prarit Bhargava <prarit@redhat.com> Cc: Richard Weinberger <richard.weinberger@gmail.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Josh Boyer <jwboyer@fedoraproject.org> Cc: Rob Landley <rob@landley.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04cma: add placement specifier for "cma=" kernel parameterAkinobu Mita
Currently, "cma=" kernel parameter is used to specify the size of CMA, but we can't specify where it is located. We want to locate CMA below 4GB for devices only supporting 32-bit addressing on 64-bit systems without iommu. This enables to specify the placement of CMA by extending "cma=" kernel parameter. Examples: 1. locate 64MB CMA below 4GB by "cma=64M@0-4G" 2. locate 64MB CMA exact at 512MB by "cma=64M@512M" Note that the DMA contiguous memory allocator on x86 assumes that page_address() works for the pages to allocate. So this change requires to limit end address of contiguous memory area upto max_pfn_mapped to prevent from locating it on highmem area by the argument of dma_contiguous_reserve(). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Don Dutile <ddutile@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04Merge tag 'pm+acpi-3.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm into next Pull ACPI and power management updates from Rafael Wysocki: "ACPICA is the leader this time (63 commits), followed by cpufreq (28 commits), devfreq (15 commits), system suspend/hibernation (12 commits), ACPI video and ACPI device enumeration (10 commits each). We have no major new features this time, but there are a few significant changes of how things work. The most visible one will probably be that we are now going to create platform devices rather than PNP devices by default for ACPI device objects with _HID. That was long overdue and will be really necessary to be able to use the same drivers for the same hardware blocks on ACPI and DT-based systems going forward. We're not expecting fallout from this one (as usual), but it's something to watch nevertheless. The second change having a chance to be visible is that ACPI video will now default to using native backlight rather than the ACPI backlight interface which should generally help systems with broken Win8 BIOSes. We're hoping that all problems with the native backlight handling that we had previously have been addressed and we are in a good enough shape to flip the default, but this change should be easy enough to revert if need be. In addition to that, the system suspend core has a new mechanism to allow runtime-suspended devices to stay suspended throughout system suspend/resume transitions if some extra conditions are met (generally, they are related to coordination within device hierarchy). However, enabling this feature requires cooperation from the bus type layer and for now it has only been implemented for the ACPI PM domain (used by ACPI-enumerated platform devices mostly today). Also, the acpidump utility that was previously shipped as a separate tool will now be provided by the upstream ACPICA along with the rest of ACPICA code, which will allow it to be more up to date and better supported, and we have one new cpuidle driver (ARM clps711x). The rest is improvements related to certain specific use cases, cleanups and fixes all over the place. Specifics: - ACPICA update to upstream version 20140424. That includes a number of fixes and improvements related to things like GPE handling, table loading, headers, memory mapping and unmapping, DSDT/SSDT overriding, and the Unload() operator. The acpidump utility from upstream ACPICA is included too. From Bob Moore, Lv Zheng, David Box, David Binderman, and Colin Ian King. - Fixes and cleanups related to ACPI video and backlight interfaces from Hans de Goede. That includes blacklist entries for some new machines and using native backlight by default. - ACPI device enumeration changes to create platform devices rather than PNP devices for ACPI device objects with _HID by default. PNP devices will still be created for the ACPI device object with device IDs corresponding to real PNP devices, so that change should not break things left and right, and we're expecting to see more and more ACPI-enumerated platform devices in the future. From Zhang Rui and Rafael J Wysocki. - Updates for the ACPI LPSS (Low-Power Subsystem) driver allowing it to handle system suspend/resume on Asus T100 correctly. From Heikki Krogerus and Rafael J Wysocki. - PM core update introducing a mechanism to allow runtime-suspended devices to stay suspended over system suspend/resume transitions if certain additional conditions related to coordination within device hierarchy are met. Related PM documentation update and ACPI PM domain support for the new feature. From Rafael J Wysocki. - Fixes and improvements related to the "freeze" sleep state. They affect several places including cpuidle, PM core, ACPI core, and the ACPI battery driver. From Rafael J Wysocki and Zhang Rui. - Miscellaneous fixes and updates of the ACPI core from Aaron Lu, Bjørn Mork, Hanjun Guo, Lan Tianyu, and Rafael J Wysocki. - Fixes and cleanups for the ACPI processor and ACPI PAD (Processor Aggregator Device) drivers from Baoquan He, Manuel Schölling, Tony Camuso, and Toshi Kani. - System suspend/resume optimization in the ACPI battery driver from Lan Tianyu. - OPP (Operating Performance Points) subsystem updates from Chander Kashyap, Mark Brown, and Nishanth Menon. - cpufreq core fixes, updates and cleanups from Srivatsa S Bhat, Stratos Karafotis, and Viresh Kumar. - Updates, fixes and cleanups for the Tegra, powernow-k8, imx6q, s5pv210, nforce2, and powernv cpufreq drivers from Brian Norris, Jingoo Han, Paul Bolle, Philipp Zabel, Stratos Karafotis, and Viresh Kumar. - intel_pstate driver fixes and cleanups from Dirk Brandewie, Doug Smythies, and Stratos Karafotis. - Enabling the big.LITTLE cpufreq driver on arm64 from Mark Brown. - Fix for the cpuidle menu governor from Chander Kashyap. - New ARM clps711x cpuidle driver from Alexander Shiyan. - Hibernate core fixes and cleanups from Chen Gang, Dan Carpenter, Fabian Frederick, Pali Rohár, and Sebastian Capella. - Intel RAPL (Running Average Power Limit) driver updates from Jacob Pan. - PNP subsystem updates from Bjorn Helgaas and Fabian Frederick. - devfreq core updates from Chanwoo Choi and Paul Bolle. - devfreq updates for exynos4 and exynos5 from Chanwoo Choi and Bartlomiej Zolnierkiewicz. - turbostat tool fix from Jean Delvare. - cpupower tool updates from Prarit Bhargava, Ramkumar Ramachandra and Thomas Renninger. - New ACPI ec_access.c tool for poking at the EC in a safe way from Thomas Renninger" * tag 'pm+acpi-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (187 commits) ACPICA: Namespace: Remove _PRP method support. intel_pstate: Improve initial busy calculation intel_pstate: add sample time scaling intel_pstate: Correct rounding in busy calculation intel_pstate: Remove C0 tracking PM / hibernate: fixed typo in comment ACPI: Fix x86 regression related to early mapping size limitation ACPICA: Tables: Add mechanism to control early table checksum verification. ACPI / scan: use platform bus type by default for _HID enumeration ACPI / scan: always register ACPI LPSS scan handler ACPI / scan: always register memory hotplug scan handler ACPI / scan: always register container scan handler ACPI / scan: Change the meaning of missing .attach() in scan handlers ACPI / scan: introduce platform_id device PNP type flag ACPI / scan: drop unsupported serial IDs from PNP ACPI scan handler ID list ACPI / scan: drop IDs that do not comply with the ACPI PNP ID rule ACPI / PNP: use device ID list for PNPACPI device enumeration ACPI / scan: .match() callback for ACPI scan handlers ACPI / battery: wakeup the system only when necessary power_supply: allow power supply devices registered w/o wakeup source ...
2014-06-03Merge branch 'acpi-video'Rafael J. Wysocki
* acpi-video: ACPI / video: Add 4 new models to the use_native_backlight DMI list ACPI / video: Add use native backlight quirk for the ThinkPad W530 ACPI / video: Unregister the backlight device if a raw one shows up later backlight: Add backlight device (un)registration notification nouveau: Don't check acpi_video_backlight_support() before registering backlight acer-wmi: Add Aspire 5741 to video_vendor_dmi_table acer-wmi: Switch to acpi_video_unregister_backlight ACPI / video: Add an acpi_video_unregister_backlight function ACPI / video: Don't register acpi_video_resume notifier without backlight devices ACPI / video: change acpi-video brightness_switch_enabled default to 0
2014-06-03Merge branch 'acpica'Rafael J. Wysocki
* acpica: (63 commits) ACPICA: Namespace: Remove _PRP method support. ACPI: Fix x86 regression related to early mapping size limitation ACPICA: Tables: Add mechanism to control early table checksum verification. ACPICA: acpidump: Fix repetitive table dump in -n mode. ACPI: Clean up acpi_os_map/unmap_memory() to eliminate __iomem. ACPICA: Clean up redudant definitions already defined elsewhere ACPICA: Linux headers: Add <asm/acenv.h> to remove mis-ordered inclusion of <asm/acpi.h> ACPICA: Linux headers: Add <acpi/platform/aclinuxex.h> ACPICA: Linux headers: Remove ACPI_PREEMPTION_POINT() due to no usages. ACPICA: Update version to 20140424. ACPICA: Comment/format update, no functional change. ACPICA: Events: Update GPE handling and initialization code. ACPICA: Remove extraneous error message for large number of GPEs. ACPICA: Tables: Remove old mechanism to validate if XSDT contains NULL entries. ACPICA: Tables: Add new mechanism to skip NULL entries in RSDT and XSDT. ACPICA: acpidump: Add support to force using RSDT. ACPICA: Back port of improvements on exception code. ACPICA: Back port of _PRP update. ACPICA: acpidump: Fix truncated RSDP signature validation. ACPICA: Linux header: Add support for stubbed externals. ...
2014-06-03Merge branch 'pm-sleep'Rafael J. Wysocki
* pm-sleep: PM / hibernate: fixed typo in comment PM / sleep: unregister wakeup source when disabling device wakeup PM / sleep: Introduce command line argument for sleep state enumeration PM / sleep: Use valid_state() for platform-dependent sleep states only PM / sleep: Add state field to pm_states[] entries PM / sleep: Update device PM documentation to cover direct_complete PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily PM / hibernate: Fix memory corruption in resumedelay_setup() PM / hibernate: convert simple_strtoul to kstrtoul PM / hibernate: Documentation: Fix script for unswapping PM / hibernate: no kernel_power_off when pm_power_off NULL PM / hibernate: use unsigned local variables in swsusp_show_speed()
2014-06-03Merge tag 'tty-3.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty into next Pull tty/serial driver updates from Greg KH: "Here is the big tty / serial driver pull request for 3.16-rc1. A variety of different serial driver fixes and updates and additions, nothing huge, and no real major core tty changes at all. All have been in linux-next for a while" * tag 'tty-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (84 commits) Revert "serial: imx: remove the DMA wait queue" serial: kgdb_nmi: Improve console integration with KDB I/O serial: kgdb_nmi: Switch from tasklets to real timers serial: kgdb_nmi: Use container_of() to locate private data serial: cpm_uart: No LF conversion in put_poll_char() serial: sirf: Fix compilation failure console: Remove superfluous readonly check console: Use explicit pointer type for vc_uni_pagedir* fields vgacon: Fix & cleanup refcounting ARM: tty: Move HVC DCC assembly to arch/arm tty/hvc/hvc_console: Fix wakeup of HVC thread on hvc_kick() drivers/tty/n_hdlc.c: replace kmalloc/memset by kzalloc vt: emulate 8- and 24-bit colour codes. printk/of_serial: fix serial console cessation part way through boot. serial: 8250_dma: check the result of TX buffer mapping serial: uart: add hw flow control support configuration tty/serial: at91: add interrupts for modem control lines tty/serial: at91: use mctrl_gpio helpers tty/serial: Add GPIOLIB helpers for controlling modem lines ARM: at91: gpio: implement get_direction ...
2014-06-01ACPI: Fix x86 regression related to early mapping size limitationLv Zheng
The following warning message is triggered: WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:136 __early_ioremap+0x11f/0x1f2() Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 3.15.0-rc1-00017-g86dfc6f3-dirty #298 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.99.99.x036.091920111209 09/19/2011 0000000000000009 ffffffff81b75c40 ffffffff817c627b 0000000000000000 ffffffff81b75c78 ffffffff81067b5d 000000000000007b 8000000000000563 00000000b96b20dc 0000000000000001 ffffffffff300e0c ffffffff81b75c88 Call Trace: [<ffffffff817c627b>] dump_stack+0x45/0x56 [<ffffffff81067b5d>] warn_slowpath_common+0x7d/0xa0 [<ffffffff81067c3a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81d4b9d5>] __early_ioremap+0x11f/0x1f2 [<ffffffff81d4bc5b>] early_ioremap+0x13/0x15 [<ffffffff81d2b8f3>] __acpi_map_table+0x13/0x18 [<ffffffff817b8d1a>] acpi_os_map_memory+0x26/0x14e [<ffffffff813ff018>] acpi_tb_acquire_table+0x42/0x70 [<ffffffff813ff086>] acpi_tb_validate_table+0x27/0x37 [<ffffffff813ff0e5>] acpi_tb_verify_table+0x22/0xd8 [<ffffffff813ff6a8>] acpi_tb_install_non_fixed_table+0x60/0x1c9 [<ffffffff81d61024>] acpi_tb_parse_root_table+0x218/0x26a [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120 [<ffffffff81d610cd>] acpi_initialize_tables+0x57/0x59 [<ffffffff81d5f25d>] acpi_table_init+0x1b/0x99 [<ffffffff81d2bca0>] acpi_boot_table_init+0x1e/0x85 [<ffffffff81d23043>] setup_arch+0x99d/0xcc6 [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120 [<ffffffff81d1bbbe>] start_kernel+0x8b/0x415 [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120 [<ffffffff81d1b5ee>] x86_64_start_reservations+0x2a/0x2c [<ffffffff81d1b72e>] x86_64_start_kernel+0x13e/0x14d ---[ end trace 11ae599a1898f4e7 ]--- when installing the following table during early stage: ACPI: SSDT 0x00000000B9638018 07A0C4 (v02 INTEL S2600CP 00004000 INTL 20100331) The regression is caused by the size limitation of the x86 early IO mapping. The root cause is: 1. ACPICA doesn't split IO memory mapping and table mapping; 2. Linux x86 OSL implements acpi_os_map_memory() using a size limited fix-map mechanism during early boot stage, which is more suitable for only IO mappings. This patch fixes this issue by utilizing acpi_gbl_verify_table_checksum to disable the table mapping during early stage and enabling it again for the late stage. In this way, the normal code path is not affected. Then after the code related to the root cause is cleaned up, the early checksum verification can be easily re-enabled. A new boot parameter - acpi_force_table_verification is introduced for the platforms that require the checksum verification to stop loading bad tables. This fix also covers the checksum verification for the table overrides. Now large tables can also be overridden using the initrd override mechanism. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Reported-and-tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-28m68k: Multi-platform EARLY_PRINTKFinn Thain
Make the boot console available to more m68k platforms by leveraging the head.S debug console. The boot console is enabled by the "earlyprintk" command line argument which is how most other architectures do this. This is a change of behaviour for the Mac but does not negatively impact the common use-case which is not debugging. This is also a change of behaviour for other platforms because it means the serial port stays quiet when CONFIG_EARLY_PRINTK is not enabled. This is also an improvement for the common use-case. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Stephen N Chivers <schivers@csc.com.au> [Geert: CONSOLE_DEBUG should depend on CONFIG_FONT_SUPPORT] Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2014-05-26PM / sleep: Introduce command line argument for sleep state enumerationRafael J. Wysocki
On some systems the platform doesn't support neither PM_SUSPEND_MEM nor PM_SUSPEND_STANDBY, so PM_SUSPEND_FREEZE is the only available system sleep state. However, some user space frameworks only use the "mem" and (sometimes) "standby" sleep state labels, so the users of those systems need to modify user space in order to be able to use system suspend at all and that is not always possible. For this reason, add a new kernel command line argument, relative_sleep_states, allowing the users of those systems to change the way in which the kernel assigns labels to system sleep states. Namely, for relative_sleep_states=1, the "mem", "standby" and "freeze" labels will enumerate the available system sleem states from the deepest to the shallowest, respectively, so that "mem" is always present in /sys/power/state and the other state strings may or may not be presend depending on what is supported by the platform. Update system sleep states documentation to reflect this change. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-14Documentation: Update kernel-parameters.txRusty Russell
1) __setup() is messy, prefer module_param and core_param. 2) Document -- 3) Document modprobe scraping /proc/cmdline. 4) Document handing of leftover parameters to init. 5) Document use of quotes to protect whitespace. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-05-11x86, rdrand: When nordrand is specified, disable RDSEED as wellH. Peter Anvin
One can logically expect that when the user has specified "nordrand", the user doesn't want any use of the CPU random number generator, neither RDRAND nor RDSEED, so disable both. Reported-by: Stephan Mueller <smueller@chronox.de> Cc: Theodore Ts'o <tytso@mit.edu> Link: http://lkml.kernel.org/r/21542339.0lFnPSyGRS@myon.chronox.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-07ACPI / video: change acpi-video brightness_switch_enabled default to 0Hans de Goede
acpi-video is unique in that it not only generates brightness up/down keypresses, but also (sometimes) actively changes the brightness itself. This presents an inconsistent kernel interface to userspace, basically there are 2 different scenarios, depending on the laptop model: 1) On some laptops a brightness up/down keypress means: show a brightness osd with the current brightness, iow it is a brightness has changed notification. 2) Where as on (a lot of) other laptops it means a brightness up/down key was pressed, deal with it. Most of the desktop environments interpret any press as in scenario 2, and change the brightness up / down as a response to the key events, causing it to be changed twice, once by acpi-video and once by the DE. With the new default for video.use_native_backlight we will be moving even more laptops over to behaving as in scenario 2. Making the remaining laptops even more of a weird exception. Also note that it is hard to detect scenario 1 properly in userspace, and AFAIK none of the DE-s deals with it. Therefor this commit changes the default of brightness_switch_enabled to 0 making its behavior consistent with all the other backlight drivers. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-28Merge back earlier ACPICA material.Rafael J. Wysocki
2014-04-24tty/serial: add arm/arm64 semihosting earlyconRob Herring
Add earlycon support for the arm/arm64 semihosting debug serial interface. This allows enabling a debug console when early_params are processed. This is based on the arm64 earlyprintk smh support and is intended to replace it. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24tty/serial: pl011: add generic earlycon supportRob Herring
Add earlycon support for the pl011 serial port. This allows enabling the pl011 for console when early_params are processed. This is based on the arm64 earlyprintk support and is intended to replace it. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-20ACPICA: Tables: Avoid SSDT installation with acpi_gbl_disable_ssdt_table_load.Lv Zheng
It is reported that when acpi_gbl_disable_ssdt_table_load is specified, user still can see it installed into /sys/firmware/acpi/tables on Linux boxes. This is because the option only stops table "loading", but doesn't stop table "installing", thus it is still in the acpi_gbl_root_table_list. With previous cleanups, it is possible to prevent SSDT installations to make it not such confusing. The global variable is also renamed. Lv Zheng. Signed-off-by: Lv Zheng <lv.zheng@intel.com> [rjw: Subject] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-16Documentation/serial: Delete obsolete driver documentationJean Delvare
These serial drivers were removed in kernel v3.1, so we can drop their documentation files and references to their magic numbers and parameters. There are still references to these old drivers in Documentation/devices.txt but I'm afraid they can't be removed. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Rob Landley <rob@landley.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-11Merge tag 'pm+acpi-3.15-rc1-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI and power management fixes and updates from Rafael Wysocki: "This is PM and ACPI material that has emerged over the last two weeks and one fix for a CPU hotplug regression introduced by the recent CPU hotplug notifiers registration series. Included are intel_idle and turbostat updates from Len Brown (these have been in linux-next for quite some time), a new cpufreq driver for powernv (that might spend some more time in linux-next, but BenH was asking me so nicely to push it for 3.15 that I couldn't resist), some cpufreq fixes and cleanups (including fixes for some silly breakage in a couple of cpufreq drivers introduced during the 3.14 cycle), assorted ACPI cleanups, wakeup framework documentation fixes, a new sysfs attribute for cpuidle and a new command line argument for power domains diagnostics. Specifics: - Fix for a recently introduced CPU hotplug regression in ARM KVM from Ming Lei. - Fixes for breakage in the at32ap, loongson2_cpufreq, and unicore32 cpufreq drivers introduced during the 3.14 cycle (-stable material) from Chen Gang and Viresh Kumar. - New powernv cpufreq driver from Vaidyanathan Srinivasan, with bits from Gautham R Shenoy and Srivatsa S Bhat. - Exynos cpufreq driver fix preventing it from being included into multiplatform builds that aren't supported by it from Sachin Kamat. - cpufreq cleanups related to the usage of the driver_data field in struct cpufreq_frequency_table from Viresh Kumar. - cpufreq ppc driver cleanup from Sachin Kamat. - Intel BayTrail support for intel_idle and ACPI idle from Len Brown. - Intel CPU model 54 (Atom N2000 series) support for intel_idle from Jan Kiszka. - intel_idle fix for Intel Ivy Town residency targets from Len Brown. - turbostat updates (Intel Broadwell support and output cleanups) from Len Brown. - New cpuidle sysfs attribute for exporting C-states' target residency information to user space from Daniel Lezcano. - New kernel command line argument to prevent power domains enabled by the bootloader from being turned off even if they are not in use (for diagnostics purposes) from Tushar Behera. - Fixes for wakeup sysfs attributes documentation from Geert Uytterhoeven. - New ACPI video blacklist entry for ThinkPad Helix from Stephen Chandler Paul. - Assorted ACPI cleanups and a Kconfig help update from Jonghwan Choi, Zhihui Zhang, Hanjun Guo" * tag 'pm+acpi-3.15-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (28 commits) ACPI: Update the ACPI spec information in Kconfig arm, kvm: fix double lock on cpu_add_remove_lock cpuidle: sysfs: Export target residency information cpufreq: ppc: Remove duplicate inclusion of fsl_soc.h cpufreq: create another field .flags in cpufreq_frequency_table cpufreq: use kzalloc() to allocate memory for cpufreq_frequency_table cpufreq: don't print value of .driver_data from core cpufreq: ia64: don't set .driver_data to index cpufreq: powernv: Select CPUFreq related Kconfig options for powernv cpufreq: powernv: Use cpufreq_frequency_table.driver_data to store pstate ids cpufreq: powernv: cpufreq driver for powernv platform cpufreq: at32ap: don't declare local variable as static cpufreq: loongson2_cpufreq: don't declare local variable as static cpufreq: unicore32: fix typo issue for 'clk' cpufreq: exynos: Disable on multiplatform build PM / wakeup: Correct presence vs. emptiness of wakeup_* attributes PM / domains: Add pd_ignore_unused to keep power domains enabled ACPI / dock: Drop dock_device_ids[] table ACPI / video: Favor native backlight interface for ThinkPad Helix ACPI / thermal: Fix wrong variable usage in debug statement ...
2014-04-07doc/kernel-parameters.txt: add early_ioremap_debugMark Salter
Add description of early_ioremap_debug kernel parameter. Signed-off-by: Mark Salter <msalter@redhat.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07PM / domains: Add pd_ignore_unused to keep power domains enabledTushar Behera
Keep all power-domains already enabled by bootloader on, even if no driver has claimed them. This is useful for debug and development, but should not be needed on a platform with proper driver support. Signed-off-by: Tushar Behera <tushar.behera@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-02Merge tag 'pm+acpi-3.15-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI and power management updates from Rafael Wysocki: "These are commits that were not quite ready when I sent the original pull request for 3.15-rc1 several days ago, but they have spent some time in linux-next since then and appear to be good to go. All of them are fixes and cleanups. Specifics: - Remaining changes from upstream ACPICA release 20140214 that introduce code to automatically serialize the execution of methods creating any named objects which really cannot be executed in parallel with each other anyway (previously ACPICA attempted to address that by aborting methods upon conflict detection, but that wasn't reliable enough and led to other issues). From Bob Moore and Lv Zheng. - intel_pstate fix to use del_timer_sync() instead of del_timer() in the exit path before freeing the timer structure from Dirk Brandewie (original patch from Thomas Gleixner). - cpufreq fix related to system resume from Viresh Kumar. - Serialization of frequency transitions in cpufreq that involve PRECHANGE and POSTCHANGE notifications to avoid ordering issues resulting from race conditions. From Srivatsa S Bhat and Viresh Kumar. - Revert of an ACPI processor driver change that was based on a specific interpretation of the ACPI spec which may not be correct (the relevant part of the spec appears to be incomplete). From Hanjun Guo. - Runtime PM core cleanups and documentation updates from Geert Uytterhoeven. - PNP core cleanup from Michael Opdenacker" * tag 'pm+acpi-3.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: Make cpufreq_notify_transition & cpufreq_notify_post_transition static cpufreq: Convert existing drivers to use cpufreq_freq_transition_{begin|end} cpufreq: Make sure frequency transitions are serialized intel_pstate: Use del_timer_sync in intel_pstate_cpu_stop cpufreq: resume drivers before enabling governors PM / Runtime: Spelling s/competing/completing/ PM / Runtime: s/foo_process_requests/foo_process_next_request/ PM / Runtime: GENERIC_SUBSYS_PM_OPS is gone PM / Runtime: Correct documented return values for generic PM callbacks PM / Runtime: Split line longer than 80 characters PM / Runtime: dev_pm_info.runtime_error is signed Revert "ACPI / processor: Make it possible to get APIC ID via GIC" ACPICA: Enable auto-serialization as a default kernel behavior. ACPICA: Ignore sync_level for methods that have been auto-serialized. ACPICA: Add additional named objects for the auto-serialize method scan. ACPICA: Add auto-serialization support for ill-behaved control methods. ACPICA: Remove global option to serialize all control methods. PNP: remove deprecated IRQF_DISABLED
2014-04-02Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso changes from Peter Anvin: "This is the revamp of the 32-bit vdso and the associated cleanups. This adds timekeeping support to the 32-bit vdso that we already have in the 64-bit vdso. Although 32-bit x86 is legacy, it is likely to remain in the embedded space for a very long time to come. This removes the traditional COMPAT_VDSO support; the configuration variable is reused for simply removing the 32-bit vdso, which will produce correct results but obviously suffer a performance penalty. Only one beta version of glibc was affected, but that version was unfortunately included in one OpenSUSE release. This is not the end of the vdso cleanups. Stefani and Andy have agreed to continue work for the next kernel cycle; in fact Andy has already produced another set of cleanups that came too late for this cycle. An incidental, but arguably important, change is that this ensures that unused space in the VVAR page is properly zeroed. It wasn't before, and would contain whatever garbage was left in memory by BIOS or the bootloader. Since the VVAR page is accessible to user space this had the potential of information leaks" * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86, vdso: Fix the symbol versions on the 32-bit vDSO x86, vdso, build: Don't rebuild 32-bit vdsos on every make x86, vdso: Actually discard the .discard sections x86, vdso: Fix size of get_unmapped_area() x86, vdso: Finish removing VDSO32_PRELINK x86, vdso: Move more vdso definitions into vdso.h x86: Load the 32-bit vdso in place, just like the 64-bit vdsos x86, vdso32: handle 32 bit vDSO larger one page x86, vdso32: Disable stack protector, adjust optimizations x86, vdso: Zero-pad the VVAR page x86, vdso: Add 32 bit VDSO time support for 64 bit kernel x86, vdso: Add 32 bit VDSO time support for 32 bit kernel x86, vdso: Patch alternatives in the 32-bit VDSO x86, vdso: Introduce VVAR marco for vdso32 x86, vdso: Cleanup __vdso_gettimeofday() x86, vdso: Replace VVAR(vsyscall_gtod_data) by gtod macro x86, vdso: __vdso_clock_gettime() cleanup x86, vdso: Revamp vclock_gettime.c mm: Add new func _install_special_mapping() to mmap.c x86, vdso: Make vsyscall_gtod_data handling x86 generic ...
2014-04-01Merge tag 'pm+acpi-3.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "The majority of this material spent some time in linux-next, some of it even several weeks. There are a few relatively fresh commits in it, but they are mostly fixes and simple cleanups. ACPI took the lead this time, both in terms of the number of commits and the number of modified lines of code, cpufreq follows and there are a few changes in the PM core and in cpuidle too. A new feature that already got some LWN.net's attention is the device PM QoS extension allowing latency tolerance requirements to be propagated from leaf devices to their ancestors with hardware interfaces for specifying latency tolerance. That should help systems with hardware-driven power management to avoid going too far with it in cases when there are latency tolerance constraints. There also are some significant changes in the ACPI core related to the way in which hotplug notifications are handled. They affect PCI hotplug (ACPIPHP) and the ACPI dock station code too. The bottom line is that all those notification now go through the root notify handler and are propagated to the interested subsystems by means of callbacks instead of having to install a notify handler for each device object that we can potentially get hotplug notifications for. In addition to that ACPICA will now advertise "Windows 2013" compatibility for _OSI, because some systems out there don't work correctly if that is not done (some of them don't even boot). On the system suspend side of things, all of the device suspend and resume callbacks, except for ->prepare() and ->complete(), are now going to be executed asynchronously as that turns out to speed up system suspend and resume on some platforms quite significantly and we have a few more optimizations in that area. Apart from that, there are some new device IDs and fixes and cleanups all over. In particular, the system suspend and resume handling by cpufreq should be improved and the cpuidle menu governor should be a bit more robust now. Specifics: - Device PM QoS support for latency tolerance constraints on systems with hardware interfaces allowing such constraints to be specified. That is necessary to prevent hardware-driven power management from becoming overly aggressive on some systems and to prevent power management features leading to excessive latencies from being used in some cases. - Consolidation of the handling of ACPI hotplug notifications for device objects. This causes all device hotplug notifications to go through the root notify handler (that was executed for all of them anyway before) that propagates them to individual subsystems, if necessary, by executing callbacks provided by those subsystems (those callbacks are associated with struct acpi_device objects during device enumeration). As a result, the code in question becomes both smaller in size and more straightforward and all of those changes should not affect users. - ACPICA update, including fixes related to the handling of _PRT in cases when it is broken and the addition of "Windows 2013" to the list of supported "features" for _OSI (which is necessary to support systems that work incorrectly or don't even boot without it). Changes from Bob Moore and Lv Zheng. - Consolidation of ACPI _OST handling from Jiang Liu. - ACPI battery and AC fixes allowing unusual system configurations to be handled by that code from Alexander Mezin. - New device IDs for the ACPI LPSS driver from Chiau Ee Chew. - ACPI fan and thermal optimizations related to system suspend and resume from Aaron Lu. - Cleanups related to ACPI video from Jean Delvare. - Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan Tianyu, Paul Bolle, Tomasz Nowicki. - Intel RAPL (Running Average Power Limits) driver cleanups from Jacob Pan. - intel_pstate fixes and cleanups from Dirk Brandewie. - cpufreq fixes related to system suspend/resume handling from Viresh Kumar. - cpufreq core fixes and cleanups from Viresh Kumar, Stratos Karafotis, Saravana Kannan, Rashika Kheria, Joe Perches. - cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob Herring. - cpuidle fixes related to the menu governor from Tuukka Tikkanen. - cpuidle fix related to coupled CPUs handling from Paul Burton. - Asynchronous execution of all device suspend and resume callbacks, except for ->prepare and ->complete, during system suspend and resume from Chuansheng Liu. - Delayed resuming of runtime-suspended devices during system suspend for the PCI bus type and ACPI PM domain. - New set of PM helper routines to allow device runtime PM callbacks to be used during system suspend and resume more easily from Ulf Hansson. - Assorted fixes and cleanups in the PM core from Geert Uytterhoeven, Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella. - devfreq fix from Saravana Kannan" * tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits) PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs PM / sleep: Correct whitespace errors in <linux/pm.h> intel_pstate: Set core to min P state during core offline cpufreq: Add stop CPU callback to cpufreq_driver interface cpufreq: Remove unnecessary braces cpufreq: Fix checkpatch errors and warnings cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs MAINTAINERS: Reorder maintainer addresses for PM and ACPI PM / Runtime: Update runtime_idle() documentation for return value meaning video / output: Drop display output class support fujitsu-laptop: Drop unneeded include acer-wmi: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / gpu / drm: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / video: fix ACPI_VIDEO dependencies cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} cpufreq: Do not allow ->setpolicy drivers to provide ->target cpufreq: arm_big_little: set 'physical_cluster' for each CPU cpufreq: arm_big_little: make vexpress driver depend on bL core driver ACPI / button: Add ACPI Button event via netlink routine ACPI: Remove duplicate definitions of PREFIX ...
2014-03-31Merge branch 'x86-kaslr-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kaslr update from Ingo Molnar: "This adds kernel module load address randomization" * 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kaslr: fix module lock ordering problem x86, kaslr: randomize module base load address