- 14 Dec, 2015 21 commits
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Marc Zyngier authored
In order to run C code in HYP, we must make sure that the kernel's RO section is mapped into HYP (otherwise things break badly). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
So far, we've implemented the new world switch with a completely different namespace, so that we could have both implementation compiled in. Let's take things one step further by adding weak aliases that have the same names as the original implementation. The weak attributes allows the new implementation to be overriden by the old one, and everything still work. At a later point, we'll be able to simply drop the old code, and everything will hopefully keep working, thanks to the aliases we have just added. This also saves us repainting all the callers. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Add the entry points for HYP mode (both for hypercalls and exception handling). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the TLB handling as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the fpsimd save restore, keeping the lazy part in assembler (as returning to C would be overkill). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
KVM so far relies on code patching, and is likely to use it more in the future. The main issue is that our alternative system works at the instruction level, while we'd like to have alternatives at the function level. In order to cope with this, add the "hyp_alternate_select" macro that outputs a brief sequence of code that in turn can be patched, allowing an alternative function to be selected. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
Contrary to the previous patch, the guest entry is fairly different from its assembly counterpart, mostly because it is only concerned with saving/restoring the GP registers, and nothing else. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
Implement the debug save restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the 32bit system register save/restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the system register save/restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
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Marc Zyngier authored
Implement the timer save restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
Implement the vgic-v3 save restore as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
We store GICv3 LRs in reverse order so that the CPU can save/restore them in rever order as well (don't ask why, the design is crazy), and yet generate memory traffic that doesn't completely suck. We need this macro to be available to the C version of save/restore. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
Implement the vgic-v2 save restore (mostly) as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
In order to expose the various EL2 services that are private to the hypervisor, add a new hyp.h file. So far, it only contains mundane things such as section annotation and VA manipulation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Mark Rutland authored
Rather than crafting custom macros for reading/writing each system register provide generics accessors, read_sysreg and write_sysreg, for this purpose. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Suzuki Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Amit Tomar authored
It would add guest exit statistics to debugfs, this can be helpful while measuring KVM performance. [ Renamed some of the field names - Christoffer ] Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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Jisheng Zhang authored
vgic_io_ops is only referenced within vgic.c, so it can be declared static. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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Linus Torvalds authored
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- 13 Dec, 2015 8 commits
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Peter Zijlstra authored
Jan Stancek reported that I wrecked things for him by fixing things for Vladimir :/ His report was due to an UNINTERRUPTIBLE wait getting -EINTR, which should not be possible, however my previous patch made this possible by unconditionally checking signal_pending(). We cannot use current->state as was done previously, because the instruction after the store to that variable it can be changed. We must instead pass the initial state along and use that. Fixes: 68985633 ("sched/wait: Fix signal handling in bit wait helpers") Reported-by: Jan Stancek <jstancek@redhat.com> Reported-by: Chris Mason <clm@fb.com> Tested-by: Jan Stancek <jstancek@redhat.com> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> Tested-by: Chris Mason <clm@fb.com> Reviewed-by: Paul Turner <pjt@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: tglx@linutronix.de Cc: Oleg Nesterov <oleg@redhat.com> Cc: hpa@zytor.com Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds authored
Pull NFS client bugfix from Trond Myklebust: "SUNRPC: Fix a NFSv4.1 callback channel regression" * tag 'nfs-for-4.4-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: SUNRPC: Fix callback channel
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fixlets from Thomas Gleixner: "Two trivial fixes which add missing header fileas and forward declarations so the code will compile even when the magic include chains are different" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gic-v3: Add missing include for barrier.h irqchip/gic-v3: Add missing struct device_node declaration
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Thomas Gleixner: "A single fix to unbreak a clocksource driver which has more than 32bit counter width" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: Mmio: remove artificial 32bit limitation
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds authored
Pull fpga driver fixes from Greg KH: "Only two small fpga driver fixes here, both have been in linux-next for a while, and resolve some reported issues" * tag 'char-misc-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: fpga manager: Fix firmware resource leak on error fpga manager: remove label
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/stagingLinus Torvalds authored
Pull staging driver fixes from Greg KH: "Here are a few staging and IIO driver fixes for 4.4-rc5. All of them resolve reported problems and have been in linux-next for a while. Nothing major here, just small fixes where needed" * tag 'staging-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: lustre: echo_copy.._lsm() dereferences userland pointers directly iio: adc: spmi-vadc: add missing of_node_put iio: fix some warning messages iio: light: apds9960: correct ->last_busy count iio: lidar: return -EINVAL on invalid signal staging: iio: dummy: complete IIO events delivery to userspace
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usbLinus Torvalds authored
Pull USB driver fixes from Greg KH: "Here are a number of small USB fixes for 4.4-rc5. All of them have been in linux-next. The majority are gadget and phy issues, with a few new quirks and device ids added as well" * tag 'usb-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (32 commits) USB: add quirk for devices with broken LPM xhci: fix usb2 resume timing and races. usb: musb: fail with error when no DMA controller set usb: gadget: uvc: fix permissions of configfs attributes usb: musb: core: Fix pm runtime for deferred probe usb: phy: msm: fix a possible NULL dereference USB: host: ohci-at91: fix a crash in ohci_hcd_at91_overcurrent_irq usb: Quiet down false peer failure messages usb: xhci: fix config fail of FS hub behind a HS hub with MTT xhci: Fix memory leak in xhci_pme_acpi_rtd3_enable() usb: Use the USB_SS_MULT() macro to decode burst multiplier for log message USB: whci-hcd: add check for dma mapping error usb: core : hub: Fix BOS 'NULL pointer' kernel panic USB: quirks: Apply ALWAYS_POLL to all ELAN devices usb-storage: Fix scsi-sd failure "Invalid field in cdb" for USB adapter JMicron USB: quirks: Fix another ELAN touchscreen usb: dwc3: gadget: don't prestart interrupt endpoints USB: serial: Another Infineon flash loader USB ID USB: cdc_acm: Ignore Infineon Flash Loader utility USB: cp210x: Remove CP2110 ID from compatibility list ...
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds authored
Pull ARM SoC fixes from Arnd Bergmann: "Here are a bunch of small bug fixes for various ARM platforms, nothing really sticks out this week, most of either fixes bugs in code that was just added in 4.4, or that has been broken for many years without anyone noticing. at91/sama5d2: - fix sama5de hardware setup of sd/mmc interface - proper selection of pinctrl drivers. PIO4 is necessary for sama5d2 berlin: - fix incorrect clock input for SDIO exynos: - Fix potential NULL pointer dereference in Exynos PMU driver. imx: - Fix vf610 SAI clock configuration bug which is discovered by the newly added master mode support in SAI audio driver. - Fix buggy L2 cache latency values in vf610 device trees, which may cause system hang when cpu runs at a higher frequency. ixp4xx: - fix prototypes for readl/writel functions ls2080a: - use little-endian register access for GPIO and SDHCI omap: - Fix clock source for ARM TWD and global timers on am437x - Always select REGULATOR_FIXED_VOLTAGE for omap2+ instead of when MACH_OMAP3_PANDORA is selected - Fix SPI DMA handles for dm816x as only some were mapped - Fix up mbox cells for dm816x to make mailbox usable pxa: - use PWM lookup table for all ezx machines s3c24xx: - Remove incorrect __init annotation from s3c24xx cpufreq driver structures. versatile: - fix PCI IRQ mapping on Versatile PB" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ls2080a/dts: Add little endian property for GPIO IP block dt-bindings: define little-endian property for QorIQ GPIO ARM64: dts: ls2080a: fix eSDHC endianness ARM: dts: vf610: use reset values for L2 cache latencies ARM: pxa: use PWM lookup table for all machines ARM: dts: berlin: add 2nd clock for BG2Q sdhci0 and sdhci1 ARM: dts: berlin: correct BG2Q's sdhci2 2nd clock ARM: dts: am4372: fix clock source for arm twd and global timers ARM: at91: fix pinctrl driver selection ARM: at91/dt: add always-on to 1.8V regulator ARM: dts: vf610: fix clock definition for SAI2 ARM: imx: clk-vf610: fix SAI clock tree ARM: ixp4xx: fix read{b,w,l} return types irqchip/versatile-fpga: Fix PCI IRQ mapping on Versatile PB ARM: OMAP2+: enable REGULATOR_FIXED_VOLTAGE ARM: dts: add dm816x missing spi DT dma handles ARM: dts: add dm816x missing #mbox-cells cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf
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- 12 Dec, 2015 11 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: - opal-irqchip: Fix double endian conversion from Alistair Popple - cxl: Set endianess of kernel contexts from Frederic Barrat - sbc8641: drop bogus PHY IRQ entries from DTS file from Paul Gortmaker - Revert "powerpc/eeh: Don't unfreeze PHB PE after reset" from Andrew Donnellan * tag 'powerpc-4.4-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: Revert "powerpc/eeh: Don't unfreeze PHB PE after reset" powerpc/sbc8641: drop bogus PHY IRQ entries from DTS file cxl: Set endianess of kernel contexts powerpc/opal-irqchip: Fix double endian conversion
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "17 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: MIPS: fix DMA contiguous allocation sh64: fix __NR_fgetxattr ocfs2: fix SGID not inherited issue mm/oom_kill.c: avoid attempting to kill init sharing same memory drivers/base/memory.c: prohibit offlining of memory blocks with missing sections tmpfs: fix shmem_evict_inode() warnings on i_blocks mm/hugetlb.c: fix resv map memory leak for placeholder entries mm: hugetlb: call huge_pte_alloc() only if ptep is null kernel: remove stop_machine() Kconfig dependency mm: kmemleak: mark kmemleak_init prototype as __init mm: fix kerneldoc on mem_cgroup_replace_page osd fs: __r4w_get_page rely on PageUptodate for uptodate MAINTAINERS: make Vladimir co-maintainer of the memory controller mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress mm: fix swapped Movable and Reclaimable in /proc/pagetypeinfo memcg: fix memory.high target mm: hugetlb: fix hugepage memory leak caused by wrong reserve count
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git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linuxLinus Torvalds authored
Pull parisc fixes from Helge Deller: "Fix the boot crash on Mako machines with Huge Pages, prevent a panic with SATA controllers (and others) by correctly calculating the IOMMU space, hook up the mlock2 syscall and drop unneeded code in the parisc pci code" * 'parisc-4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: Disable huge pages on Mako machines parisc: Wire up mlock2 syscall parisc: Remove unused pcibios_init_bus() parisc iommu: fix panic due to trying to allocate too large region
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block layer fixes from Jens Axboe: "A set of fixes for the current series. This contains: - A bunch of fixes for lightnvm, should be the last round for this series. From Matias and Wenwei. - A writeback detach inode fix from Ilya, also marked for stable. - A block (though it says SCSI) fix for an OOPS in SCSI runtime power management. - Module init error path fixes for null_blk from Minfei" * 'for-linus' of git://git.kernel.dk/linux-block: null_blk: Fix error path in module initialization lightnvm: do not compile in debugging by default lightnvm: prevent gennvm module unload on use lightnvm: fix media mgr registration lightnvm: replace req queue with nvmdev for lld lightnvm: comments on constants lightnvm: check mm before use lightnvm: refactor spin_unlock in gennvm_get_blk lightnvm: put blks when luns configure failed lightnvm: use flags in rrpc_get_blk block: detach bdev inode from its wb in __blkdev_put() SCSI: Fix NULL pointer dereference in runtime PM
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 fixes from Catalin Marinas: - Update the linker script to use L1_CACHE_BYTES instead of hard-coded 64. We recently changed L1_CACHE_BYTES to 128 - Improve race condition reporting on set_pte_at() and change the BUG to WARN_ONCE. With hardware update of the accessed/dirty state, we need to ensure that set_pte_at() does not inadvertently override hardware updated state. The patch also makes the checks ignore !pte_valid() new entries * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Improve error reporting on set_pte_at() checks arm64: update linker script to increased L1_CACHE_BYTES value
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Qais Yousef authored
Recent changes to how GFP_ATOMIC is defined seems to have broken the condition to use mips_alloc_from_contiguous() in mips_dma_alloc_coherent(). I couldn't bottom out the exact change but I think it's this commit d0164adc ("mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd"). GFP_ATOMIC has multiple bits set and the check for !(gfp & GFP_ATOMIC) isn't enough. The reason behind this condition is to check whether we can potentially do a sleeping memory allocation. Use gfpflags_allow_blocking() instead which should be more robust. Signed-off-by: Qais Yousef <qais.yousef@imgtec.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Dmitry V. Levin authored
According to arch/sh/kernel/syscalls_64.S and common sense, __NR_fgetxattr has to be defined to 259, but it doesn't. Instead, it's defined to 269, which is of course used by another syscall, __NR_sched_setaffinity in this case. This bug was found by strace test suite. Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Junxiao Bi authored
Commit 8f1eb487 ("ocfs2: fix umask ignored issue") introduced an issue, SGID of sub dir was not inherited from its parents dir. It is because SGID is set into "inode->i_mode" in ocfs2_get_init_inode(), but is overwritten by "mode" which don't have SGID set later. Fixes: 8f1eb487 ("ocfs2: fix umask ignored issue") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Acked-by: Srinivas Eeda <srinivas.eeda@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Chen Jie authored
It's possible that an oom killed victim shares an ->mm with the init process and thus oom_kill_process() would end up trying to kill init as well. This has been shown in practice: Out of memory: Kill process 9134 (init) score 3 or sacrifice child Killed process 9134 (init) total-vm:1868kB, anon-rss:84kB, file-rss:572kB Kill process 1 (init) sharing same memory ... Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 And this will result in a kernel panic. If a process is forked by init and selected for oom kill while still sharing init_mm, then it's likely this system is in a recoverable state. However, it's better not to try to kill init and allow the machine to panic due to unkillable processes. [rientjes@google.com: rewrote changelog] [akpm@linux-foundation.org: fix inverted test, per Ben] Signed-off-by: Chen Jie <chenjie6@huawei.com> Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Li Zefan <lizefan@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Seth Jennings authored
Commit bdee237c ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems") and 982792c7 ("x86, mm: probe memory block size for generic x86 64bit") introduced large block sizes for x86. This made it possible to have multiple sections per memory block where previously, there was a only every one section per block. Since blocks consist of contiguous ranges of section, there can be holes in the blocks where sections are not present. If one attempts to offline such a block, a crash occurs since the code is not designed to deal with this. This patch is a quick fix to gaurd against the crash by not allowing blocks with non-present sections to be offlined. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=107781Signed-off-by: Seth Jennings <sjennings@variantweb.net> Reported-by: Andrew Banman <abanman@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Russ Anderson <rja@sgi.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Dmitry Vyukov provides a little program, autogenerated by syzkaller, which races a fault on a mapping of a sparse memfd object, against truncation of that object below the fault address: run repeatedly for a few minutes, it reliably generates shmem_evict_inode()'s WARN_ON(inode->i_blocks). (But there's nothing specific to memfd here, nor to the fstat which it happened to use to generate the fault: though that looked suspicious, since a shmem_recalc_inode() had been added there recently. The same problem can be reproduced with open+unlink in place of memfd_create, and with fstatfs in place of fstat.) v3.7 commit 0f3c42f5 ("tmpfs: change final i_blocks BUG to WARNING") explains one cause of such a warning (a race with shmem_writepage to swap), and possible solutions; but we never took it further, and this syzkaller incident turns out to have a different cause. shmem_getpage_gfp()'s error recovery, when a freshly allocated page is then found to be beyond eof, looks plausible - decrementing the alloced count that was just before incremented - but in fact can go wrong, if a racing thread (the truncator, for example) gets its shmem_recalc_inode() in just after our delete_from_page_cache(). delete_from_page_cache() decrements nrpages, that shmem_recalc_inode() will balance the books by decrementing alloced itself, then our decrement of alloced take it one too low: leading to the WARNING when the object is finally evicted. Once the new page has been exposed in the page cache, shmem_getpage_gfp() must leave it to shmem_recalc_inode() itself to get the accounting right in all cases (and not fall through from "trunc:" to "decused:"). Adjust that error recovery block; and the reinitialization of info and sbinfo can be removed too. While we're here, fix shmem_writepage() to avoid the original issue: it will be safe against a racing shmem_recalc_inode(), if it merely increments swapped before the shmem_delete_from_page_cache() which decrements nrpages (but it must then do its own shmem_recalc_inode() before that, while still in balance, instead of after). (Aside: why do we shmem_recalc_inode() here in the swap path? Because its raison d'etre is to cope with clean sparse shmem pages being reclaimed behind our back: so here when swapping is a good place to look for that case.) But I've not now managed to reproduce this bug, even without the patch. I don't see why I didn't do that earlier: perhaps inhibited by the preference to eliminate shmem_recalc_inode() altogether. Driven by this incident, I do now have a patch to do so at last; but still want to sit on it for a bit, there's a couple of questions yet to be resolved. Signed-off-by: Hugh Dickins <hughd@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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