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2017-06-26mm: 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> [wt: backport to 4.11: adjust context] [wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide] [wt: backport to 4.4: adjust context ; drop ppc hugetlb_radix changes] [wt: backport to 3.18: adjust context ; no FOLL_POPULATE ; s390 uses generic arch_get_unmapped_area()] Signed-off-by: Willy Tarreau <w@1wt.eu> [gkh: minor build fixes for 3.18] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20USB: uas: Add a new NO_REPORT_LUNS quirkHans de Goede
[ Upstream commit 1363074667a6b7d0507527742ccd7bbed5e3ceaa ] 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. Cc: stable@vger.kernel.org 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> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-05-17uas: Add US_FL_MAX_SECTORS_240 flagHans de Goede
[ Upstream commit ee136af4a064c2f61e2025873584d2c7ec93f4ae ] 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. Cc: stable@vger.kernel.org # 3.16 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: Sasha Levin <sasha.levin@oracle.com>
2015-01-27Input: 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07USB: Update default usb-storage delay_use value in kernel-parameters.txtMark Knibbs
Back in 2010 the default usb-storage delay_use time was reduced from 5 to 1 second (commit a4a47bc03fe520e95e0c4212bf97c86545fb14f9), but kernel-parameters.txt wasn't updated to reflect that. Signed-off-by: Mark Knibbs <markk@clara.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: "A bunch of fixes for minor defects reported by Coverity, a few driver fixups and revert of i8042.nomux change so that we are once again enable active MUX mode if box claims to support it" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Revert "Input: i8042 - disable active multiplexing by default" Input: altera_ps2 - use correct type for irq return value Input: altera_ps2 - write to correct register when disabling interrupts Input: max77693-haptic - fix potential overflow Input: psmouse - remove unneeded check in psmouse_reconnect() Input: vsxxxaa - fix code dropping bytes from queue Input: ims-pcu - fix dead code in ims_pcu_ofn_reg_addr_store() Input: opencores-kbd - fix error handling Input: wm97xx - adapt parameters to tosa touchscreen. Input: i8042 - quirks for Fujitsu Lifebook A544 and Lifebook AH544 Input: stmpe-keypad - fix valid key line bitmask Input: soc_button_array - update calls to gpiod_get*()
2014-10-31Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds
Pull documentation fixes from Jonathan Corbet: "So this is my first pull request since I rashly agreed to look after the documentation subtree. It contains some typo fixes, a few minor documentation improvements, and, most importantly, fixes for a couple of build problems in various bits of sample code. I fully intend to start sending pull requests with signed tags. However, due to poor planning on my part and the general obnoxiousness of life, I'm 2000 miles away from my private key which is sitting on a powered-down machine. This should be fixed before my next request. Meanwhile git.lwn.net is a machine under my control, the patches are all trivial, and all have done time in linux-next" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: Documentation/SubmittingPatches: Reported-by tags and permission Documentation: remove outdated references to the linux-next wiki Documentation: Restrict TSC test code to x86 doc: kernel-parameters.txt: Add ide-generic.probe-mask vdso: don't require 64-bit math in standalone test Documentation: Add CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF case Documentation: Add default kmemleak off case in kernel-parameters.txt Docs: Document that the sticky bit is understood by hugetlbfs DocBook: Reduce noise from make cleandocs Documentation: fix vdso_standalone_test_x86 on 32-bit Documentation: dt-bindings: Explain order in patch series Documentation/ABI/testing/sysfs-ibft: fix a typo
2014-10-31Revert "Input: i8042 - disable active multiplexing by default"Dmitry Torokhov
This reverts commit 68da166491655bc54051bf04c78ce648e2e33508. It turns out that the assertion about scope of regressions due to always keeping keyboard controller in legacy mode was proven wrong. There are laptops, such as Clevo W650SH, that only have internal touchpad (no external PS/2 ports), that require active multiplexing mode to switch the touchpad (Elantech) into native mode instead of basic PS/2 emulation. Reported-by: Roel Aaij <roel.aaij@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-27doc: kernel-parameters.txt: Add ide-generic.probe-maskMaciej W. Rozycki
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> [ jc: wording tweaked slightly ] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-10-24Documentation: Add default kmemleak off case in kernel-parameters.txtMasanari Iida
Add missing explanation about CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF=y case. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-10-23Merge branch 'x86-efi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 EFI updates from Peter Anvin: "This patchset falls under the "maintainers that grovel" clause in the v3.18-rc1 announcement. We had intended to push it late in the merge window since we got it into the -tip tree relatively late. Many of these are relatively simple things, but there are a couple of key bits, especially Ard's and Matt's patches" * 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) rtc: Disable EFI rtc for x86 efi: rtc-efi: Export platform:rtc-efi as module alias efi: Delete the in_nmi() conditional runtime locking efi: Provide a non-blocking SetVariable() operation x86/efi: Adding efi_printks on memory allocationa and pci.reads x86/efi: Mark initialization code as such x86/efi: Update comment regarding required phys mapped EFI services x86/efi: Unexport add_efi_memmap variable x86/efi: Remove unused efi_call* macros efi: Resolve some shadow warnings arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format() ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format() x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format() efi: Introduce efi_md_typeattr_format() efi: Add macro for EFI_MEMORY_UCE memory attribute x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi arm64/efi: uefi_init error handling fix efi: Add kernel param efi=noruntime lib: Add a generic cmdline parse function parse_option_str ...
2014-10-21Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux Pull more powerpc updates from Michael Ellerman: "Here's some more updates for powerpc for 3.18. They are a bit late I know, though must are actually bug fixes. In my defence I nearly cut the top of my finger off last weekend in a gruesome bike maintenance accident, so I spent a good part of the week waiting around for doctors. True story, I can send photos if you like :) Probably the most interesting fix is the sys_call_table one, which enables syscall tracing for powerpc. There's a fix for HMI handling for old firmware, more endian fixes for firmware interfaces, more EEH fixes, Anton fixed our routine that gets the current stack pointer, and a few other misc bits" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (22 commits) powerpc: Only do dynamic DMA zone limits on platforms that need it powerpc: sync pseries_le_defconfig with pseries_defconfig powerpc: Add printk levels to setup_system output powerpc/vphn: NUMA node code expects big-endian powerpc/msi: Use WARN_ON() in msi bitmap selftests powerpc/msi: Fix the msi bitmap alignment tests powerpc/eeh: Block CFG upon frozen Shiner adapter powerpc/eeh: Don't collect logs on PE with blocked config space powerpc/eeh: Block PCI config access upon frozen PE powerpc/pseries: Drop config requests in EEH accessors powerpc/powernv: Drop config requests in EEH accessors powerpc/eeh: Rename flag EEH_PE_RESET to EEH_PE_CFG_BLOCKED powerpc/eeh: Fix condition for isolated state powerpc/pseries: Make CPU hotplug path endian safe powerpc/pseries: Use dump_stack instead of show_stack powerpc: Rename __get_SP() to current_stack_pointer() powerpc: Reimplement __get_SP() as a function not a define powerpc/numa: Add ability to disable and debug topology updates powerpc/numa: check error return from proc_create powerpc/powernv: Fallback to old HMI handling behavior for old firmware ...
2014-10-19Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull second round of input updates from Dmitry Torokhov: "Mostly simple bug fixes, although we do have one brand new driver for Microchip AR1021 i2c touchscreen. Also there is the change to stop trying to use i8042 active multiplexing by default (it is still possible to activate it via i8042.nomux=0 on boxes that implement it)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: xpad - add Thrustmaster as Xbox 360 controller vendor Input: xpad - add USB ID for Thrustmaster Ferrari 458 Racing Wheel Input: max77693-haptic - fix state check in imax77693_haptic_disable() Input: xen-kbdfront - free grant table entry in xenkbd_disconnect_backend Input: alps - fix v4 button press recognition Input: i8042 - disable active multiplexing by default Input: i8042 - add noloop quirk for Asus X750LN Input: synaptics - gate forcepad support by DMI check Input: Add Microchip AR1021 i2c touchscreen Input: cros_ec_keyb - add of match table Input: serio - avoid negative serio device numbers Input: avoid negative input device numbers Input: automatically set EV_ABS bit in input_set_abs_params Input: adp5588-keys - cancel workqueue in failure path Input: opencores-kbd - switch to using managed resources Input: evdev - fix EVIOCG{type} ioctl
2014-10-15Merge tag 'clk-for-linus-3.18' of ↵Linus Torvalds
git://git.linaro.org/people/mike.turquette/linux Pull clock tree updates from Mike Turquette: "The clk tree changes for 3.18 are dominated by clock drivers. Mostly fixes and enhancements to existing drivers as well as new drivers. This tag contains a bit more arch code than I usually take due to some OMAP2+ changes. Additionally it contains the restart notifier handlers which are merged as a dependency into several trees. The PXA changes are the only messy part. Due to having a stable tree I had to revert one patch and follow up with one more fix near the tip of this tag. Some dead code is introduced but it will soon become live code after 3.18-rc1 is released as the rest of the PXA family is converted over to the common clock framework. Another trend in this tag is that multiple vendors have started to push the complexity of changing their CPU frequency into the clock driver, whereas this used to be done in CPUfreq drivers. Changes to the clk core include a generic gpio-clock type and a clk_set_phase() function added to the top-level clk.h api. Due to some confusion on the fbdev mailing list the kernel boot parameters documentation was updated to further explain the clk_ignore_unused parameter, which is often required by users of the simplefb driver. Finally some fixes to the locking around the clock debugfs stuff was done to prevent deadlocks when interacting with other subsystems." * tag 'clk-for-linus-3.18' of git://git.linaro.org/people/mike.turquette/linux: (99 commits) clk: pxa clocks build system fix Revert "arm: pxa: Transition pxa27x to clk framework" clk: samsung: register restart handlers for s3c2412 and s3c2443 clk: rockchip: add restart handler clk: rockchip: rk3288: i2s_frac adds flag to set parent's rate doc/kernel-parameters.txt: clarify clk_ignore_unused arm: pxa: Transition pxa27x to clk framework dts: add devicetree bindings for pxa27x clocks clk: add pxa27x clock drivers arm: pxa: add clock pll selection bits clk: dts: document pxa clock binding clk: add pxa clocks infrastructure clk: gpio-gate: Ensure gpiod_ APIs are prototyped clk: ti: dra7-atl-clock: Mark the device as pm_runtime_irq_safe clk: ti: LLVMLinux: Move __init outside of type definition clk: ti: consider the fact that of_clk_get() might return an error clk: ti: dra7-atl-clock: fix a memory leak clk: ti: change clock init to use generic of_clk_init clk: hix5hd2: add I2C clocks clk: hix5hd2: add watchdog0 clocks ...
2014-10-13Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes in this cycle were: - changes related to No-CBs CPUs and NO_HZ_FULL - RCU-tasks implementation - torture-test updates - miscellaneous fixes - locktorture updates - RCU documentation updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (81 commits) workqueue: Use cond_resched_rcu_qs macro workqueue: Add quiescent state between work items locktorture: Cleanup header usage locktorture: Cannot hold read and write lock locktorture: Fix __acquire annotation for spinlock irq locktorture: Support rwlocks rcu: Eliminate deadlock between CPU hotplug and expedited grace periods locktorture: Document boot/module parameters rcutorture: Rename rcutorture_runnable parameter locktorture: Add test scenario for rwsem_lock locktorture: Add test scenario for mutex_lock locktorture: Make torture scripting account for new _runnable name locktorture: Introduce torture context locktorture: Support rwsems locktorture: Add infrastructure for torturing read locks torture: Address race in module cleanup locktorture: Make statistics generic locktorture: Teach about lock debugging locktorture: Support mutexes locktorture: Add documentation ...
2014-10-13powerpc/numa: Add ability to disable and debug topology updatesNishanth Aravamudan
We have hit a few customer issues with the topology update code (VPHN and PRRN). It would be nice to be able to debug the notifications coming from the hypervisor in both cases to the LPAR, as well as to disable responding to the notifications at boot-time, to narrow down the source of the problems. Add a basic level of such functionality, similar to the numa= command-line parameter. We already have a toggle in /proc/powerpc/topology_updates that allows run-time enabling/disabling, so the updates can be started at run-time if desired. But the bugs we've run into have occured during boot or very shortly after coming to login, and have resulted in a broken NUMA topology. Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-10-12Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris. Mostly ima, selinux, smack and key handling updates. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits) integrity: do zero padding of the key id KEYS: output last portion of fingerprint in /proc/keys KEYS: strip 'id:' from ca_keyid KEYS: use swapped SKID for performing partial matching KEYS: Restore partial ID matching functionality for asymmetric keys X.509: If available, use the raw subjKeyId to form the key description KEYS: handle error code encoded in pointer selinux: normalize audit log formatting selinux: cleanup error reporting in selinux_nlmsg_perm() KEYS: Check hex2bin()'s return when generating an asymmetric key ID ima: detect violations for mmaped files ima: fix race condition on ima_rdwr_violation_check and process_measurement ima: added ima_policy_flag variable ima: return an error code from ima_add_boot_aggregate() ima: provide 'ima_appraise=log' kernel option ima: move keyring initialization to ima_init() PKCS#7: Handle PKCS#7 messages that contain no X.509 certs PKCS#7: Better handling of unsupported crypto KEYS: Overhaul key identification when searching for asymmetric keys KEYS: Implement binary asymmetric key ID handling ...
2014-10-11Input: i8042 - disable active multiplexing by defaultDmitry Torokhov
Active multiplexing is a nice feature as it allows several pointing devices (such as touchpad and external mouse) use their native protocols at the same time. Unfortunately many manufacturers do not implement the feature properly even though they advertise it. The problematic implementations are never fixed, since Windows by default does not use this mode, and move from one BIOS/model of laptop to another. When active multiplexing is broken turning it on usually results in touchpad, keyboard, or both unresponsive. With PS/2 usage on decline (most of PS/2 devices in use nowadays are internal laptop touchpads), I expect number of users who have laptops with working MUX implementation, docking stations with external PS/2 ports, and who are still using external PS/2 mice, to be rather small. Let's flip the default to be OFF and allow activating it through i8042.nomux=0 kernel option. We'll also keep DMI table where we can record known good models. Acked-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-09Merge branch 'akpm' (fixes from Andrew Morton)Linus Torvalds
Merge patch-bomb from Andrew Morton: - part of OCFS2 (review is laggy again) - procfs - slab - all of MM - zram, zbud - various other random things: arch, filesystems. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (164 commits) nosave: consolidate __nosave_{begin,end} in <asm/sections.h> include/linux/screen_info.h: remove unused ORIG_* macros kernel/sys.c: compat sysinfo syscall: fix undefined behavior kernel/sys.c: whitespace fixes acct: eliminate compile warning kernel/async.c: switch to pr_foo() include/linux/blkdev.h: use NULL instead of zero include/linux/kernel.h: deduplicate code implementing clamp* macros include/linux/kernel.h: rewrite min3, max3 and clamp using min and max alpha: use Kbuild logic to include <asm-generic/sections.h> frv: remove deprecated IRQF_DISABLED frv: remove unused cpuinfo_frv and friends to fix future build error zbud: avoid accessing last unused freelist zsmalloc: simplify init_zspage free obj linking mm/zsmalloc.c: correct comment for fullness group computation zram: use notify_free to account all free notifications zram: report maximum used memory zram: zram memory size limitation zsmalloc: change return value unit of zs_get_total_size_bytes zsmalloc: move pages_allocated to zs_pool ...
2014-10-09CMA: document cma=0Jean Delvare
It isn't obvious that CMA can be disabled on the kernel's command line, so document it. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09mm/slab_common: commonize slab merge logicJoonsoo Kim
Slab merge is good feature to reduce fragmentation. Now, it is only applied to SLUB, but, it would be good to apply it to SLAB. This patch is preparation step to apply slab merge to SLAB by commonizing slab merge logic. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09Merge tag 'pm+acpi-3.18-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: "Features-wise, to me the most important this time is a rework of wakeup interrupts handling in the core that makes them work consistently across all of the available sleep states, including suspend-to-idle. Many thanks to Thomas Gleixner for his help with this work. Second is an update of the generic PM domains code that has been in need of some care for quite a while. Unused code is being removed, DT support is being added and domains are now going to be attached to devices in bus type code in analogy with the ACPI PM domain. The majority of work here was done by Ulf Hansson who also has been the most active developer this time. Apart from this we have a traditional ACPICA update, this time to upstream version 20140828 and a few ACPI wakeup interrupts handling patches on top of the general rework mentioned above. There also are several cpufreq commits including renaming the cpufreq-cpu0 driver to cpufreq-dt, as this is what implements generic DT-based cpufreq support, and a new DT-based idle states infrastructure for cpuidle. In addition to that, the ACPI LPSS driver is updated, ACPI support for Apple machines is improved, a few bugs are fixed and a few cleanups are made all over. Finally, the Adaptive Voltage Scaling (AVS) subsystem now has a tree maintained by Kevin Hilman that will be merged through the PM tree. Numbers-wise, the generic PM domains update takes the lead this time with 32 non-merge commits, second is cpufreq (15 commits) and the 3rd place goes to the wakeup interrupts handling rework (13 commits). Specifics: - Rework the handling of wakeup IRQs by the IRQ core such that all of them will be switched over to "wakeup" mode in suspend_device_irqs() and in that mode the first interrupt will abort system suspend in progress or wake up the system if already in suspend-to-idle (or equivalent) without executing any interrupt handlers. Among other things that eliminates the wakeup-related motivation to use the IRQF_NO_SUSPEND interrupt flag with interrupts which don't really need it and should not use it (Thomas Gleixner and Rafael Wysocki) - Switch over ACPI to handling wakeup interrupts with the help of the new mechanism introduced by the above IRQ core rework (Rafael Wysocki) - Rework the core generic PM domains code to eliminate code that's not used, add DT support and add a generic mechanism by which devices can be added to PM domains automatically during enumeration (Ulf Hansson, Geert Uytterhoeven and Tomasz Figa). - Add debugfs-based mechanics for debugging generic PM domains (Maciej Matraszek). - ACPICA update to upstream version 20140828. Included are updates related to the SRAT and GTDT tables and the _PSx methods are in the METHOD_NAME list now (Bob Moore and Hanjun Guo). - Add _OSI("Darwin") support to the ACPI core (unfortunately, that can't really be done in a straightforward way) to prevent Thunderbolt from being turned off on Apple systems after boot (or after resume from system suspend) and rework the ACPI Smart Battery Subsystem (SBS) driver to work correctly with Apple platforms (Matthew Garrett and Andreas Noever). - ACPI LPSS (Low-Power Subsystem) driver update cleaning up the code, adding support for 133MHz I2C source clock on Intel Baytrail to it and making it avoid using UART RTS override with Auto Flow Control (Heikki Krogerus). - ACPI backlight updates removing the video_set_use_native_backlight quirk which is not necessary any more, making the code check the list of output devices returned by the _DOD method to avoid creating acpi_video interfaces that won't work and adding a quirk for Lenovo Ideapad Z570 (Hans de Goede, Aaron Lu and Stepan Bujnak) - New Win8 ACPI OSI quirks for some Dell laptops (Edward Lin) - Assorted ACPI code cleanups (Fabian Frederick, Rasmus Villemoes, Sudip Mukherjee, Yijing Wang, and Zhang Rui) - cpufreq core updates and cleanups (Viresh Kumar, Preeti U Murthy, Rasmus Villemoes) - cpufreq driver updates: cpufreq-cpu0/cpufreq-dt (driver name change among other things), ppc-corenet, powernv (Viresh Kumar, Preeti U Murthy, Shilpasri G Bhat, Lucas Stach) - cpuidle support for DT-based idle states infrastructure, new ARM64 cpuidle driver, cpuidle core cleanups (Lorenzo Pieralisi, Rasmus Villemoes) - ARM big.LITTLE cpuidle driver updates: support for DT-based initialization and Exynos5800 compatible string (Lorenzo Pieralisi, Kevin Hilman) - Rework of the test_suspend kernel command line argument and a new trace event for console resume (Srinivas Pandruvada, Todd E Brandt) - Second attempt to optimize swsusp_free() (hibernation core) to make it avoid going through all PFNs which may be way too slow on some systems (Joerg Roedel) - devfreq updates (Paul Bolle, Punit Agrawal, Ãrjan Eide). - rockchip-io Adaptive Voltage Scaling (AVS) driver and AVS entry update in MAINTAINERS (Heiko Stübner, Kevin Hilman) - PM core fix related to clock management (Geert Uytterhoeven) - PM core's sysfs code cleanup (Johannes Berg)" * tag 'pm+acpi-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (105 commits) ACPI / fan: printk replacement PM / clk: Fix crash in clocks management code if !CONFIG_PM_RUNTIME PM / Domains: Rename cpu_data to cpuidle_data cpufreq: cpufreq-dt: fix potential double put of cpu OF node cpufreq: cpu0: rename driver and internals to 'cpufreq_dt' PM / hibernate: Iterate over set bits instead of PFNs in swsusp_free() cpufreq: ppc-corenet: remove duplicate update of cpu_data ACPI / sleep: Rework the handling of ACPI GPE wakeup from suspend-to-idle PM / sleep: Rename platform suspend/resume functions in suspend.c PM / sleep: Export dpm_suspend_late/noirq() and dpm_resume_early/noirq() ACPICA: Introduce acpi_enable_all_wakeup_gpes() ACPICA: Clear all non-wakeup GPEs in acpi_hw_enable_wakeup_gpe_block() ACPI / video: check _DOD list when creating backlight devices PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.h cpufreq: Replace strnicmp with strncasecmp cpufreq: powernv: Set the cpus to nominal frequency during reboot/kexec cpufreq: powernv: Set the pstate of the last hotplugged out cpu in policy->cpus to minimum cpufreq: Allow stop CPU callback to be used by all cpufreq drivers PM / devfreq: exynos: Enable building exynos PPMU as module PM / devfreq: Export helper functions for drivers ...
2014-10-08Merge tag 'tty-3.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Here's the big tty/serial driver patchset for 3.18-rc1. Lots of little things in here, some good work from Peter Hurley on the tty core, and in lots of drivers. There are also lots of other driver updates in here as well, full details in the changelogs. All have been in the linux-next tree for a while" * tag 'tty-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (99 commits) Revert "serial/core: Initialize the console pm state" tty: serial: 8250: use 32bit variable for rpm_tx_active tty: serial: msm: Add earlycon support serial/core: Initialize the console pm state serial: asc: Conditionally use readl_relaxed (COMPILE_TEST) serial: of-serial: add PM suspend/resume support m68k: AMIGA_BUILTIN_SERIAL should depend on TTY asm/uapi: Add definition of TIOC[SG]RS485 tty/metag_da: Add console_poll module parameter serial: 8250_pci: remove rts_n override from Baytrail quirk serial: cadence: Add generic earlycon support serial: imx: change the wait even to interruptiable serial: imx: terminate the RX DMA when the UART is suspending serial: imx: fix throttle/unthrottle callbacks for hardware assisted flow control serial: 8250: Add Quark X1000 to 8250_pci.c tty: omap-serial: pull out calculation from baud_is_mode16 tty: omap-serial: fix division by zero xen_hvc: no reason to write the type key on xenstore tty: serial: 8250_core: remove UART_IER_RDI in serial8250_stop_rx() tty: serial: 8250_core: use the ->line argument as a hint in serial8250_find_match_or_unused() ...
2014-10-03Merge branch 'next' into efi-next-mergeMatt Fleming
Conflicts: arch/x86/boot/compressed/eboot.c
2014-10-03efi: Add kernel param efi=noruntimeDave Young
noefi kernel param means actually disabling efi runtime, Per suggestion from Leif Lindholm efi=noruntime should be better. But since noefi is already used in X86 thus just adding another param efi=noruntime for same purpose. Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-03efi: Move noefi early param code out of x86 arch codeDave Young
noefi param can be used for arches other than X86 later, thus move it out of x86 platform code. Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-03efi: Add efi= parameter parsing to the EFI boot stubMatt Fleming
We need a way to customize the behaviour of the EFI boot stub, in particular, we need a way to disable the "chunking" workaround, used when reading files from the EFI System Partition. One of my machines doesn't cope well when reading files in 1MB chunks to a buffer above the 4GB mark - it appears that the "chunking" bug workaround triggers another firmware bug. This was only discovered with commit 4bf7111f5016 ("x86/efi: Support initrd loaded above 4G"), and that commit is perfectly valid. The symptom I observed was a corrupt initrd rather than any kind of crash. efi= is now used to specify EFI parameters in two very different execution environments, the EFI boot stub and during kernel boot. There is also a slight performance optimization by enabling efi=nochunk, but that's offset by the fact that you're more likely to run into firmware issues, at least on x86. This is the rationale behind leaving the workaround enabled by default. Also provide some documentation for EFI_READ_CHUNK_SIZE and why we're using the current value of 1MB. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Roy Franz <roy.franz@linaro.org> Cc: Maarten Lankhorst <m.b.lankhorst@gmail.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-02Merge branch 'next' of ↵James Morris
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next
2014-09-30doc/kernel-parameters.txt: clarify clk_ignore_unusedMike Turquette
Refine the definition around clk_ignore_unused, which caused some confusion recently on the linux-fbdev and linux-arm-kernel mailing lists[0]. [0] http://lkml.kernel.org/r/<20140929135358.GC30998@ulmo> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-10-01Merge commit 'v3.16' into nextJames Morris
2014-09-29Merge back earlier 'pm-sleep' material for v3.18.Rafael J. Wysocki
2014-09-28tty: serial: msm: Add earlycon supportStephen Boyd
Add support for DT based and command line based early console on platforms with the msm serial hardware. Cc: Rob Herring <robh@kernel.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-28serial: cadence: Add generic earlycon supportMichal Simek
Add earlycon support for the cadence serial port. This is based on recent patches: "tty/serial: pl011: add generic earlycon support" (sha1: 0d3c673e7881e691991b2a4745bd4f149603baa2) "tty/serial: add arm/arm64 semihosting earlycon" (sha1: d50d7269ebcb438afa346cdffce0f4e2a1b9e831) Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23uas: Add no-report-opcodes quirkHans de Goede
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 Cc: stable@vger.kernel.org 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>
2014-09-23uas: Add a quirk for rejecting ATA_12 and ATA_16 commandsHans de Goede
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. Cc: stable@vger.kernel.org # 3.16, 3.17 Signed-off-by: Hans de Goede <hdegoede@redhat.com> -- Changes in v2: Add documentation for new t and u usb-storage.quirks flags Changes in v3: Fix typo in documentation Changes in v4: Also apply the quirk to (0bc2:3312) Changes in v5: Rebased on 3.17-rc5, drop u documentation, already upstream Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull the v3.18 RCU changes from Paul E. McKenney: " * Update RCU documentation. These were posted to LKML at https://lkml.org/lkml/2014/8/28/378. * Miscellaneous fixes. These were posted to LKML at https://lkml.org/lkml/2014/8/28/386. An additional fix that eliminates a documented (but now inconvenient) deadlock between RCU hotplug and expedited grace periods was posted at https://lkml.org/lkml/2014/8/28/573. * Changes related to No-CBs CPUs and NO_HZ_FULL. These were posted to LKML at https://lkml.org/lkml/2014/8/28/412. * Torture-test updates. These were posted to LKML at https://lkml.org/lkml/2014/8/28/546 and at https://lkml.org/lkml/2014/9/11/1114. * RCU-tasks implementation. These were posted to LKML at https://lkml.org/lkml/2014/8/28/540. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-17ima: provide 'ima_appraise=log' kernel optionDmitry Kasatkin
The kernel boot parameter "ima_appraise" currently defines 'off', 'enforce' and 'fix' modes. When designing a policy and labeling the system, access to files are either blocked in the default 'enforce' mode or automatically fixed in the 'fix' mode. It is beneficial to be able to run the system in a logging only mode, without fixing it, in order to properly analyze the system. This patch adds a 'log' mode to run the system in a permissive mode and log the appraisal results. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-16locktorture: Document boot/module parametersPaul E. McKenney
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-16rcutorture: Rename rcutorture_runnable parameterPaul E. McKenney
This commit changes rcutorture_runnable to torture_runnable, which is consistent with the names of the other parameters and is a bit shorter as well. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-16Merge branch 'rcu-tasks.2014.09.10a' into HEADPaul E. McKenney
rcu-tasks.2014.09.10a: Add RCU-tasks flavor of RCU.
2014-09-09PM / sleep: Update test_suspend option documentationSrinivas Pandruvada
Updated documentation to add freeze mode and repeat capability. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-08USB: document the 'u' flag for usb-storage quirks parameterAlan Stern
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> Cc: stable <stable@vger.kernel.org> # 3.15+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-07rcu: Add stall-warning checks for RCU-tasksPaul E. McKenney
This commit adds a ten-minute RCU-tasks stall warning. The actual time is controlled by the boot/sysfs parameter rcu_task_stall_timeout, with values less than or equal to zero disabling the stall warnings. The default value is ten minutes, which means that the tasks that have not yet responded will get their stacks dumped every ten minutes, until they pass through a voluntary context switch. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07rcutorture: Add callback-flood testPaul E. McKenney
Although RCU is designed to handle arbitrary floods of callbacks, this capability is not routinely tested. This commit therefore adds a cbflood capability in which kthreads repeatedly registers large numbers of callbacks. One such kthread is created for each four CPUs (rounding up), and the test may be controlled by several cbflood_* kernel boot parameters, which control the number of bursts per flood, the number of callbacks per burst, the time between bursts, and the time between floods. The default values are large enough to exercise RCU's emergency responses to callback flooding. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: David Miller <davem@davemloft.net> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-08-13Merge branch 'x86-xsave-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/xsave changes from Peter Anvin: "This is a patchset to support the XSAVES instruction required to support context switch of supervisor-only features in upcoming silicon. This patchset missed the 3.16 merge window, which is why it is based on 3.15-rc7" * 'x86-xsave-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, xsave: Add forgotten inline annotation x86/xsaves: Clean up code in xstate offsets computation in xsave area x86/xsave: Make it clear that the XSAVE macros use (%edi)/(%rdi) Define kernel API to get address of each state in xsave area x86/xsaves: Enable xsaves/xrstors x86/xsaves: Call booting time xsaves and xrstors in setup_init_fpu_buf x86/xsaves: Save xstate to task's xsave area in __save_fpu during booting time x86/xsaves: Add xsaves and xrstors support for booting time x86/xsaves: Clear reserved bits in xsave header x86/xsaves: Use xsave/xrstor for saving and restoring user space context x86/xsaves: Use xsaves/xrstors for context switch x86/xsaves: Use xsaves/xrstors to save and restore xsave area x86/xsaves: Define a macro for handling xsave/xrstor instruction fault x86/xsaves: Define macros for xsave instructions x86/xsaves: Change compacted format xsave area header x86/alternative: Add alternative_input_2 to support alternative with two features and input x86/xsaves: Add a kernel parameter noxsaves to disable xsaves/xrstors
2014-08-07Merge tag 'stable/for-linus-3.17-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen updates from David Vrabel: - remove unused V2 grant table support - note that Konrad is xen-blkkback/front maintainer - add 'xen_nopv' option to disable PV extentions for x86 HVM guests - misc minor cleanups * tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen-pciback: Document the 'quirks' sysfs file xen/pciback: Fix error return code in xen_pcibk_attach() xen/events: drop negativity check of unsigned parameter xen/setup: Remove Identity Map Debug Message xen/events/fifo: remove a unecessary use of BM() xen/events/fifo: ensure all bitops are properly aligned even on x86 xen/events/fifo: reset control block and local HEADs on resume xen/arm: use BUG_ON xen/grant-table: remove support for V2 tables x86/xen: safely map and unmap grant frames when in atomic context MAINTAINERS: Make me the Xen block subsystem (front and back) maintainer xen: Introduce 'xen_nopv' to disable PV extensions for HVM guests.
2014-08-07Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds
Pull MIPS updates from Ralf Baechle: "This is the main pull request for 3.17. It contains: - misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy updates - MIPS ptrace updates and cleanups - various fixes that will also go to -stable - a number of cleanups and small non-critical fixes. - NUMA support for the Loongson 3. - more support for MSA - support for MAAR - various FP enhancements and fixes" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits) MIPS: jz4740: remove unnecessary null test before debugfs_remove MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive MIPS: ZBOOT: implement stack protector in compressed boot phase MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT MIPS: Bonito64: remove a duplicate define MIPS: Malta: initialise MAARs MIPS: Initialise MAARs MIPS: detect presence of MAARs MIPS: define MAAR register accessors & bits MIPS: mark MSA experimental MIPS: Don't build MSA support unless it can be used MIPS: consistently clear MSA flags when starting & copying threads MIPS: 16 byte align MSA vector context MIPS: disable preemption whilst initialising MSA MIPS: ensure MSA gets disabled during boot MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains MIPS: fix MSA context for tasks which don't use FP first MIPS: init upper 64b of vector registers when MSA is first used MIPS: save/disable MSA in lose_fpu MIPS: preserve scalar FP CSR when switching vector context ...
2014-08-07Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "Mostly cleanups and bug-fixes, with two exceptions. The first is lazy flushing of I/O-TLBs for PCI to improve performance, the second is software dirty bits in the pmd for the madvise-free implementation" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (24 commits) s390/locking: Reenable optimistic spinning s390/mm: implement dirty bits for large segment table entries KVM: s390/mm: Fix page table locking vs. split pmd lock s390/dasd: fix camel case s390/3215: fix hanging console issue s390/irq: improve displayed interrupt order in /proc/interrupts s390/seccomp: fix error return for filtered system calls s390/pci: introduce lazy IOTLB flushing for DMA unmap dasd: fix error recovery for alias devices during format dasd: fix list_del corruption during format dasd: fix unresponsive device during format dasd: use aliases for formatted devices during format s390/pci: fix kmsg component s390/kdump: Return NOTIFY_OK for all actions other than MEM_GOING_OFFLINE s390/watchdog: Fix module name in Kconfig help text s390/dasd: replace seq_printf by seq_puts s390/dasd: replace pr_warning by pr_warn s390/dasd: Move EXPORT_SYMBOL after function/variable s390/dasd: remove unnecessary null test before debugfs_remove s390/zfcp: use qdio buffer helpers ...
2014-08-06printk: allow increasing the ring buffer depending on the number of CPUsLuis R. Rodriguez
The default size of the ring buffer is too small for machines with a large amount of CPUs under heavy load. What ends up happening when debugging is the ring buffer overlaps and chews up old messages making debugging impossible unless the size is passed as a kernel parameter. An idle system upon boot up will on average spew out only about one or two extra lines but where this really matters is on heavy load and that will vary widely depending on the system and environment. There are mechanisms to help increase the kernel ring buffer for tracing through debugfs, and those interfaces even allow growing the kernel ring buffer per CPU. We also have a static value which can be passed upon boot. Relying on debugfs however is not ideal for production, and relying on the value passed upon bootup is can only used *after* an issue has creeped up. Instead of being reactive this adds a proactive measure which lets you scale the amount of contributions you'd expect to the kernel ring buffer under load by each CPU in the worst case scenario. We use num_possible_cpus() to avoid complexities which could be introduced by dynamically changing the ring buffer size at run time, num_possible_cpus() lets us use the upper limit on possible number of CPUs therefore avoiding having to deal with hotplugging CPUs on and off. This introduces the kernel configuration option LOG_CPU_MAX_BUF_SHIFT which is used to specify the maximum amount of contributions to the kernel ring buffer in the worst case before the kernel ring buffer flips over, the size is specified as a power of 2. The total amount of contributions made by each CPU must be greater than half of the default kernel ring buffer size (1 << LOG_BUF_SHIFT bytes) in order to trigger an increase upon bootup. The kernel ring buffer is increased to the next power of two that would fit the required minimum kernel ring buffer size plus the additional CPU contribution. For example if LOG_BUF_SHIFT is 18 (256 KB) you'd require at least 128 KB contributions by other CPUs in order to trigger an increase of the kernel ring buffer. With a LOG_CPU_BUF_SHIFT of 12 (4 KB) you'd require at least anything over > 64 possible CPUs to trigger an increase. If you had 128 possible CPUs the amount of minimum required kernel ring buffer bumps to: ((1 << 18) + ((128 - 1) * (1 << 12))) / 1024 = 764 KB Since we require the ring buffer to be a power of two the new required size would be 1024 KB. This CPU contributions are ignored when the "log_buf_len" kernel parameter is used as it forces the exact size of the ring buffer to an expected power of two value. [pmladek@suse.cz: fix build] Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.cz> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Tested-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Davidlohr Bueso <davidlohr@hp.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Petr Mladek <pmladek@suse.cz> Cc: Joe Perches <joe@perches.com> Cc: Arun KS <arunks.linux@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "In this release: - PKCS#7 parser for the key management subsystem from David Howells - appoint Kees Cook as seccomp maintainer - bugfixes and general maintenance across the subsystem" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (94 commits) X.509: Need to export x509_request_asymmetric_key() netlabel: shorter names for the NetLabel catmap funcs/structs netlabel: fix the catmap walking functions netlabel: fix the horribly broken catmap functions netlabel: fix a problem when setting bits below the previously lowest bit PKCS#7: X.509 certificate issuer and subject are mandatory fields in the ASN.1 tpm: simplify code by using %*phN specifier tpm: Provide a generic means to override the chip returned timeouts tpm: missing tpm_chip_put in tpm_get_random() tpm: Properly clean sysfs entries in error path tpm: Add missing tpm_do_selftest to ST33 I2C driver PKCS#7: Use x509_request_asymmetric_key() Revert "selinux: fix the default socket labeling in sock_graft()" X.509: x509_request_asymmetric_keys() doesn't need string length arguments PKCS#7: fix sparse non static symbol warning KEYS: revert encrypted key change ima: add support for measuring and appraising firmware firmware_class: perform new LSM checks security: introduce kernel_fw_from_file hook PKCS#7: Missing inclusion of linux/err.h ...