- 16 Oct, 2019 8 commits
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Thierry Reding <thierry.reding@gmail.com> Acked-by: Zhou Yanjie <zhouyanjie@zoho.com> Acked-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20191001133209.17164-1-linus.walleij@linaro.org
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Kiran Gunda authored
Add support for the PM6150 and PM6150L GPIO support to the Qualcomm PMIC GPIO binding. Signed-off-by: Kiran Gunda <kgunda@codeaurora.org> Link: https://lore.kernel.org/r/1570188039-22122-1-git-send-email-kgunda@codeaurora.orgAcked-by: Bjorn Andersson <bjorn.andersson@linaro.org> Reviewed-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Andrew Bresticker <abrestic@chromium.org> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: James Hartley <james.hartley@sondrel.com> Link: https://lore.kernel.org/r/20191001214536.18477-1-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Gregory CLEMENT <gregory.clement@bootlin.com> Cc: Marek Behún <marek.behun@nic.cz> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20191002121550.16104-1-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20191002114454.9684-1-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20191002113819.4927-1-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion: the ST pin controller errors out of adding a irqchip if the interrupt is invalid or missing or if the irqmux is not present: the irqchip should not be added if either of these errors happen, so rewrite the code to deal with that. Keep the exit path where the gpio_chip is added no matter what the status of the irq is. Cc: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Amelie Delaunay <amelie.delaunay@st.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20191001135147.29416-1-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion: at91 is a little bit special since it registers up to 3 gpio_chips with the same parent handler, but just passing girq->parent_handler and the parent on the first of them should cut it. Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20191001130645.8350-1-linus.walleij@linaro.org
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- 05 Oct, 2019 1 commit
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Chris Packham authored
Use the dev_name(dev) for the irqc->name so that we get unique names when we have multiple instances of this driver. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Link: https://lore.kernel.org/r/20191003000310.17099-3-chris.packham@alliedtelesis.co.nzAcked-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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- 04 Oct, 2019 3 commits
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Rasmus Villemoes authored
The helper pinctrl_dt_has_hogs() was introduced in 99e4f675 (pinctrl: core: Use delayed work for hogs), but the sole use then got removed shortly after in 950b0d91 (pinctrl: core: Fix regression caused by delayed work for hogs). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20190923142005.5632-1-linux@rasmusvillemoes.dkAcked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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Thierry Reding authored
Add a comment about why the call to of_match_node() cannot be replaced by of_device_get_match_data(). This will hopefully prevent people from attempting to clean this up in the future. Signed-off-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/r/20190923095400.GA11084@ulmoSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
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Colin Ian King authored
The call to pinctrl_count_index_with_args checks for a -EINVAL return however this function calls pinctrl_get_list_and_count and this can return -ENOENT. Rather than check for a specific error, fix this by checking for any error return to catch the -ENOENT case. Addresses-Coverity: ("Improper use of negative") Fixes: 003910eb ("pinctrl: Introduce TI IOdelay configuration driver") Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20190920122030.14340-1-colin.king@canonical.comAcked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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- 03 Oct, 2019 3 commits
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Brian Masney authored
Now that the GPIO core has support for hierarchical IRQ chips, convert Qualcomm's ssbi-gpio over to use these new helpers to reduce duplicated code across drivers. Signed-off-by: Brian Masney <masneyb@onstation.org> Link: https://lore.kernel.org/r/20190914111010.24384-1-masneyb@onstation.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
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Will Deacon authored
When populating the pinctrl mapping table entries for a device, the 'dev_name' field for each entry is initialised to point directly at the string returned by 'dev_name()' for the device and subsequently used by 'create_pinctrl()' when looking up the mappings for the device being probed. This is unreliable in the presence of calls to 'dev_set_name()', which may reallocate the device name string leaving the pinctrl mappings with a dangling reference. This then leads to a use-after-free every time the name is dereferenced by a device probe: | BUG: KASAN: invalid-access in strcmp+0x20/0x64 | Read of size 1 at addr 13ffffc153494b00 by task modprobe/590 | Pointer tag: [13], memory tag: [fe] | | Call trace: | __kasan_report+0x16c/0x1dc | kasan_report+0x10/0x18 | check_memory_region | __hwasan_load1_noabort+0x4c/0x54 | strcmp+0x20/0x64 | create_pinctrl+0x18c/0x7f4 | pinctrl_get+0x90/0x114 | devm_pinctrl_get+0x44/0x98 | pinctrl_bind_pins+0x5c/0x450 | really_probe+0x1c8/0x9a4 | driver_probe_device+0x120/0x1d8 Follow the example of sysfs, and duplicate the device name string before stashing it away in the pinctrl mapping entries. Cc: Linus Walleij <linus.walleij@linaro.org> Reported-by: Elena Petrova <lenaptr@google.com> Tested-by: Elena Petrova <lenaptr@google.com> Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20191002124206.22928-1-will@kernel.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
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Alexandre Belloni authored
Implement .get_multiple and .set_multiple to allow reading or setting multiple pins simultaneously. Pins in the same bank will all be switched at the same time, improving synchronization and performances. Keep the driver future proof by allowing its use on 64bits platforms if they ever appear with this IP and we end up with a mismatch between ATMEL_PIO_NPINS_PER_BANK and BITS_PER_LONG. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20190918113657.25998-1-alexandre.belloni@bootlin.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
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- 30 Sep, 2019 23 commits
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Barry Song <baohua@kernel.org> Cc: Yuping Luo <yuping.luo@csr.com> Cc: Rongjun Ying <rongjun.ying@csr.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-6-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Barry Song <baohua@kernel.org> Cc: Yuping Luo <yuping.luo@csr.com> Cc: Rongjun Ying <rongjun.ying@csr.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-5-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Tomer Maimon <tmaimon77@gmail.com> Cc: Kun Yi <kunyi@google.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-4-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Shiraz Hashim <shiraz.linux.kernel@gmail.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-3-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Joshua Henderson <joshua.henderson@microchip.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-2-linus.walleij@linaro.org
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Linus Walleij authored
We need to convert all old gpio irqchips to pass the irqchip setup along when adding the gpio_chip. For more info see drivers/gpio/TODO. For chained irqchips this is a pretty straight-forward conversion. Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190913113530.5536-1-linus.walleij@linaro.org
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linuxLinus Torvalds authored
Pull btrfs fixes from David Sterba: "A bunch of fixes that accumulated in recent weeks, mostly material for stable. Summary: - fix for regression from 5.3 that prevents to use balance convert with single profile - qgroup fixes: rescan race, accounting leak with multiple writers, potential leak after io failure recovery - fix for use after free in relocation (reported by KASAN) - other error handling fixups" * tag 'for-5.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: qgroup: Fix reserved data space leak if we have multiple reserve calls btrfs: qgroup: Fix the wrong target io_tree when freeing reserved data space btrfs: Fix a regression which we can't convert to SINGLE profile btrfs: relocation: fix use-after-free on dead relocation roots Btrfs: fix race setting up and completing qgroup rescan workers Btrfs: fix missing error return if writeback for extent buffer never started btrfs: adjust dirty_metadata_bytes after writeback failure of extent buffer Btrfs: fix selftests failure due to uninitialized i_mode in test inodes
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git://github.com/c-sky/csky-linuxLinus Torvalds authored
Pull csky updates from Guo Ren: "This round of csky subsystem just some fixups: - Fix mb() synchronization problem - Fix dma_alloc_coherent with PAGE_SO attribute - Fix cache_op failed when cross memory ZONEs - Optimize arch_sync_dma_for_cpu/device with dma_inv_range - Fix ioremap function losing - Fix arch_get_unmapped_area() implementation - Fix defer cache flush for 610 - Support kernel non-aligned access - Fix 610 vipt cache flush mechanism - Fix add zero_fp fixup perf backtrace panic - Move static keyword to the front of declaration - Fix csky_pmu.max_period assignment - Use generic free_initrd_mem() - entry: Remove unneeded need_resched() loop" * tag 'csky-for-linus-5.4-rc1' of git://github.com/c-sky/csky-linux: csky: Move static keyword to the front of declaration csky: entry: Remove unneeded need_resched() loop csky: Fixup csky_pmu.max_period assignment csky: Fixup add zero_fp fixup perf backtrace panic csky: Use generic free_initrd_mem() csky: Fixup 610 vipt cache flush mechanism csky: Support kernel non-aligned access csky: Fixup defer cache flush for 610 csky: Fixup arch_get_unmapped_area() implementation csky: Fixup ioremap function losing csky: Optimize arch_sync_dma_for_cpu/device with dma_inv_range csky/dma: Fixup cache_op failed when cross memory ZONEs csky: Fixup dma_alloc_coherent with PAGE_SO attribute csky: Fixup mb() synchronization problem
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git://git.kernel.org/pub/scm/linux/kernel/git/soc/socLinus Torvalds authored
Pull ARM SoC fixes from Olof Johansson: "A few fixes that have trickled in through the merge window: - Video fixes for OMAP due to panel-dpi driver removal - Clock fixes for OMAP that broke no-idle quirks + nfsroot on DRA7 - Fixing arch version on ASpeed ast2500 - Two fixes for reset handling on ARM SCMI" * tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: ARM: aspeed: ast2500 is ARMv6K reset: reset-scmi: add missing handle initialisation firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle() ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux ARM: dts: am3517-evm: Fix missing video ARM: dts: logicpd-torpedo-baseboard: Fix missing video ARM: omap2plus_defconfig: Fix missing video bus: ti-sysc: Fix handling of invalid clocks bus: ti-sysc: Fix clock handling for no-idle quirks
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds authored
Pull tracing fixes from Steven Rostedt: "A few more tracing fixes: - Fix a buffer overflow by checking nr_args correctly in probes - Fix a warning that is reported by clang - Fix a possible memory leak in error path of filter processing - Fix the selftest that checks for failures, but wasn't failing - Minor clean up on call site output of a memory trace event" * tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: selftests/ftrace: Fix same probe error test mm, tracing: Print symbol name for call_site in trace events tracing: Have error path in predicate_parse() free its allocated memory tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro tracing/probe: Fix to check the difference of nr_args before adding probe
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git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds authored
Pull more MMC updates from Ulf Hansson: "A couple more updates/fixes for MMC: - sdhci-pci: Add Genesys Logic GL975x support - sdhci-tegra: Recover loss in throughput for DMA - sdhci-of-esdhc: Fix DMA bug" * tag 'mmc-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: host: sdhci-pci: Add Genesys Logic GL975x support mmc: tegra: Implement ->set_dma_mask() mmc: sdhci: Let drivers define their DMA mask mmc: sdhci-of-esdhc: set DMA snooping based on DMA coherence mmc: sdhci: improve ADMA error reporting
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Krzysztof Wilczynski authored
Move the static keyword to the front of declaration of csky_pmu_of_device_ids, and resolve the following compiler warning that can be seen when building with warnings enabled (W=1): arch/csky/kernel/perf_event.c:1340:1: warning: ‘static’ is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Krzysztof Wilczynski <kw@linux.com> Signed-off-by: Guo Ren <guoren@kernel.org>
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Valentin Schneider authored
Since the enabling and disabling of IRQs within preempt_schedule_irq() is contained in a need_resched() loop, we don't need the outer arch code loop. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Guo Ren <guoren@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds authored
Pull Documentation/process update from Greg KH: "Here are two small Documentation/process/embargoed-hardware-issues.rst file updates that missed my previous char/misc pull request. The first one adds an Intel representative for the process, and the second one cleans up the text a bit more when it comes to how the disclosure rules work, as it was a bit confusing to some companies" * tag 'char-misc-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: Documentation/process: Clarify disclosure rules Documentation/process: Volunteer as the ambassador for Intel
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull more vfs updates from Al Viro: "A couple of misc patches" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: afs dynroot: switch to simple_dir_operations fs/handle.c - fix up kerneldoc
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull more cifs updates from Steve French: "Fixes from the recent SMB3 Test events and Storage Developer Conference (held the last two weeks). Here are nine smb3 patches including an important patch for debugging traces with wireshark, with three patches marked for stable. Additional fixes from last week to better handle some newly discovered reparse points, and a fix the create/mkdir path for setting the mode more atomically (in SMB3 Create security descriptor context), and one for path name processing are still being tested so are not included here" * tag '5.4-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: CIFS: Fix oplock handling for SMB 2.1+ protocols smb3: missing ACL related flags smb3: pass mode bits into create calls smb3: Add missing reparse tags CIFS: fix max ea value size fs/cifs/sess.c: Remove set but not used variable 'capabilities' fs/cifs/smb2pdu.c: Make SMB2_notify_init static smb3: fix leak in "open on server" perf counter smb3: allow decryption keys to be dumped by admin for debugging
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Mao Han authored
The csky_pmu.max_period has type u64, and BIT() can only return 32 bits unsigned long on C-SKY. The initialization for max_period will be incorrect when count_width is bigger than 32. Use BIT_ULL() Signed-off-by: Mao Han <han_mao@c-sky.com> Signed-off-by: Guo Ren <ren_guo@c-sky.com>
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Guo Ren authored
We need set fp zero to let backtrace know the end. The patch fixup perf callchain panic problem, because backtrace didn't know what is the end of fp. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Reported-by: Mao Han <han_mao@c-sky.com>
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Mike Rapoport authored
The csky implementation of free_initrd_mem() is an open-coded version of free_reserved_area() without poisoning. Remove it and make csky use the generic version of free_initrd_mem(). Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Guo Ren <guoren@kernel.org>
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Linus Torvalds authored
Merge active entropy generation updates. This is admittedly partly "for discussion". We need to have a way forward for the boot time deadlocks where user space ends up waiting for more entropy, but no entropy is forthcoming because the system is entirely idle just waiting for something to happen. While this was triggered by what is arguably a user space bug with GDM/gnome-session asking for secure randomness during early boot, when they didn't even need any such truly secure thing, the issue ends up being that our "getrandom()" interface is prone to that kind of confusion, because people don't think very hard about whether they want to block for sufficient amounts of entropy. The approach here-in is to decide to not just passively wait for entropy to happen, but to start actively collecting it if it is missing. This is not necessarily always possible, but if the architecture has a CPU cycle counter, there is a fair amount of noise in the exact timings of reasonably complex loads. We may end up tweaking the load and the entropy estimates, but this should be at least a reasonable starting point. As part of this, we also revert the revert of the ext4 IO pattern improvement that ended up triggering the reported lack of external entropy. * getrandom() active entropy waiting: Revert "Revert "ext4: make __ext4_get_inode_loc plug"" random: try to actively add entropy rather than passively wait for it
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Linus Torvalds authored
This reverts commit 72dbcf72. Instead of waiting forever for entropy that may just not happen, we now try to actively generate entropy when required, and are thus hopefully avoiding the problem that caused the nice ext4 IO pattern fix to be reverted. So revert the revert. Cc: Ahmed S. Darwish <darwish.07@gmail.com> Cc: Ted Ts'o <tytso@mit.edu> Cc: Willy Tarreau <w@1wt.eu> Cc: Alexander E. Patrakov <patrakov@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
For 5.3 we had to revert a nice ext4 IO pattern improvement, because it caused a bootup regression due to lack of entropy at bootup together with arguably broken user space that was asking for secure random numbers when it really didn't need to. See commit 72dbcf72 (Revert "ext4: make __ext4_get_inode_loc plug"). This aims to solve the issue by actively generating entropy noise using the CPU cycle counter when waiting for the random number generator to initialize. This only works when you have a high-frequency time stamp counter available, but that's the case on all modern x86 CPU's, and on most other modern CPU's too. What we do is to generate jitter entropy from the CPU cycle counter under a somewhat complex load: calling the scheduler while also guaranteeing a certain amount of timing noise by also triggering a timer. I'm sure we can tweak this, and that people will want to look at other alternatives, but there's been a number of papers written on jitter entropy, and this should really be fairly conservative by crediting one bit of entropy for every timer-induced jump in the cycle counter. Not because the timer itself would be all that unpredictable, but because the interaction between the timer and the loop is going to be. Even if (and perhaps particularly if) the timer actually happens on another CPU, the cacheline interaction between the loop that reads the cycle counter and the timer itself firing is going to add perturbations to the cycle counter values that get mixed into the entropy pool. As Thomas pointed out, with a modern out-of-order CPU, even quite simple loops show a fair amount of hard-to-predict timing variability even in the absense of external interrupts. But this tries to take that further by actually having a fairly complex interaction. This is not going to solve the entropy issue for architectures that have no CPU cycle counter, but it's not clear how (and if) that is solvable, and the hardware in question is largely starting to be irrelevant. And by doing this we can at least avoid some of the even more contentious approaches (like making the entropy waiting time out in order to avoid the possibly unbounded waiting). Cc: Ahmed Darwish <darwish.07@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Nicholas Mc Guire <hofrat@opentech.at> Cc: Andy Lutomirski <luto@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Willy Tarreau <w@1wt.eu> Cc: Alexander E. Patrakov <patrakov@gmail.com> Cc: Lennart Poettering <mzxreary@0pointer.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 29 Sep, 2019 2 commits
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Olof Johansson authored
Merge tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/fixes Fixes for omap variants Few fixes for ti-sysc interconnect target module driver for no-idle quirks that caused nfsroot to fail on some dra7 boards. And let's fixes to get LCD working again for logicpd board that got broken a while back with removal of panel-dpi driver. We need to now use generic CONFIG_DRM_PANEL_SIMPLE instead. * tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle() ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux ARM: dts: am3517-evm: Fix missing video ARM: dts: logicpd-torpedo-baseboard: Fix missing video ARM: omap2plus_defconfig: Fix missing video bus: ti-sysc: Fix handling of invalid clocks bus: ti-sysc: Fix clock handling for no-idle quirks Link: https://lore.kernel.org/r/pull-1568819401-72461@atomide.comSigned-off-by: Olof Johansson <olof@lixom.net>
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Olof Johansson authored
Merge tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/fixes ARM SCMI fixes for v5.4 Couple of fixes: one in scmi reset driver initialising missed scmi handle and an other in scmi reset API implementation fixing the assignment of reset state * tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: reset: reset-scmi: add missing handle initialisation firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset Link: https://lore.kernel.org/r/20190918142139.GA4370@bogusSigned-off-by: Olof Johansson <olof@lixom.net>
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