kernel/linux.git, branch v4.18.18

Linux 4.18.18

2018-11-10T15:49:48+00:00

x86/fpu: Fix i486 + no387 boot crash by only saving FPU registers on context switch if there is an FPU

2018-11-10T15:49:48+00:00

commit 2224d616528194b02424c91c2ee254b3d29942c3 upstream. Booting an i486 with "no387 nofxsr" ends with with the following crash: math_emulate: 0060:c101987d Kernel panic - not syncing: Math emulation needed in kernel on the first context switch in user land. The reason is that copy_fpregs_to_fpstate() tries FNSAVE which does not work as the FPU is turned off. This bug was introduced in: f1c8cd0176078 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active") Add a check for X86_FEATURE_FPU before trying to save FPU registers (we have such a check in switch_fpu_finish() already). Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org Fixes: f1c8cd0176078 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active") Link: http://lkml.kernel.org/r/20181016202525.29437-4-bigeasy@linutronix.de Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86/swiotlb: Enable swiotlb for > 4GiG RAM on 32-bit kernels

2018-11-10T15:49:48+00:00

commit 485734f3fc77c1eb77ffe138c027b9a4bf0178f3 upstream. We already build the swiotlb code for 32-bit kernels with PAE support, but the code to actually use swiotlb has only been enabled for 64-bit kernels for an unknown reason. Before Linux v4.18 we paper over this fact because the networking code, the SCSI layer and some random block drivers implemented their own bounce buffering scheme. [ mingo: Changelog fixes. ] Fixes: 21e07dba9fb1 ("scsi: reduce use of block bounce buffers") Fixes: ab74cfebafa3 ("net: remove the PCI_DMA_BUS_IS_PHYS check in illegal_highdma") Reported-by: Matthew Whitehead Signed-off-by: Christoph Hellwig Signed-off-by: Thomas Gleixner Tested-by: Matthew Whitehead Cc: konrad.wilk@oracle.com Cc: iommu@lists.linux-foundation.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181014075208.2715-1-hch@lst.de Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86/time: Correct the attribute on jiffies' definition

2018-11-10T15:49:48+00:00

commit 53c13ba8ed39e89f21a0b98f4c8a241bb44e483d upstream. Clang warns that the declaration of jiffies in include/linux/jiffies.h doesn't match the definition in arch/x86/time/kernel.c: arch/x86/kernel/time.c:29:42: warning: section does not match previous declaration [-Wsection] __visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES; ^ ./include/linux/cache.h:49:4: note: expanded from macro '__cacheline_aligned' __section__(".data..cacheline_aligned"))) ^ ./include/linux/jiffies.h:81:31: note: previous attribute is here extern unsigned long volatile __cacheline_aligned_in_smp __jiffy_arch_data jiffies; ^ ./arch/x86/include/asm/cache.h:20:2: note: expanded from macro '__cacheline_aligned_in_smp' __page_aligned_data ^ ./include/linux/linkage.h:39:29: note: expanded from macro '__page_aligned_data' #define __page_aligned_data __section(.data..page_aligned) __aligned(PAGE_SIZE) ^ ./include/linux/compiler_attributes.h:233:56: note: expanded from macro '__section' #define __section(S) __attribute__((__section__(#S))) ^ 1 warning generated. The declaration was changed in commit 7c30f352c852 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp") but wasn't updated here. Make them match so Clang no longer warns. Fixes: 7c30f352c852 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp") Signed-off-by: Nathan Chancellor Signed-off-by: Thomas Gleixner Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Nick Desaulniers Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181013005311.28617-1-natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman

x86/percpu: Fix this_cpu_read()

2018-11-10T15:49:48+00:00

commit b59167ac7bafd804c91e49ad53c6d33a7394d4c8 upstream. Eric reported that a sequence count loop using this_cpu_read() got optimized out. This is wrong, this_cpu_read() must imply READ_ONCE() because the interface is IRQ-safe, therefore an interrupt can have changed the per-cpu value. Fixes: 7c3576d261ce ("[PATCH] i386: Convert PDA into the percpu section") Reported-by: Eric Dumazet Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Acked-by: Eric Dumazet Cc: hpa@zytor.com Cc: eric.dumazet@gmail.com Cc: bp@alien8.de Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181011104019.748208519@infradead.org Signed-off-by: Greg Kroah-Hartman

x86, hibernate: Fix nosave_regions setup for hibernation

2018-11-10T15:49:47+00:00

commit cc55f7537db6af371e9c1c6a71161ee40f918824 upstream. On 32bit systems, nosave_regions(non RAM areas) located between max_low_pfn and max_pfn are not excluded from hibernation snapshot currently, which may result in a machine check exception when trying to access these unsafe regions during hibernation: [ 612.800453] Disabling lock debugging due to kernel taint [ 612.805786] mce: [Hardware Error]: CPU 0: Machine Check Exception: 5 Bank 6: fe00000000801136 [ 612.814344] mce: [Hardware Error]: RIP !INEXACT! 60:<00000000d90be566> {swsusp_save+0x436/0x560} [ 612.823167] mce: [Hardware Error]: TSC 1f5939fe276 ADDR dd000000 MISC 30e0000086 [ 612.830677] mce: [Hardware Error]: PROCESSOR 0:306c3 TIME 1529487426 SOCKET 0 APIC 0 microcode 24 [ 612.839581] mce: [Hardware Error]: Run the above through 'mcelog --ascii' [ 612.846394] mce: [Hardware Error]: Machine check: Processor context corrupt [ 612.853380] Kernel panic - not syncing: Fatal machine check [ 612.858978] Kernel Offset: 0x18000000 from 0xc1000000 (relocation range: 0xc0000000-0xf7ffdfff) This is because on 32bit systems, pages above max_low_pfn are regarded as high memeory, and accessing unsafe pages might cause expected MCE. On the problematic 32bit system, there are reserved memory above low memory, which triggered the MCE: e820 memory mapping: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009d7ff] usable [ 0.000000] BIOS-e820: [mem 0x000000000009d800-0x000000000009ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000000e0000-0x00000000000fffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000d160cfff] usable [ 0.000000] BIOS-e820: [mem 0x00000000d160d000-0x00000000d1613fff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000d1614000-0x00000000d1a44fff] usable [ 0.000000] BIOS-e820: [mem 0x00000000d1a45000-0x00000000d1ecffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000d1ed0000-0x00000000d7eeafff] usable [ 0.000000] BIOS-e820: [mem 0x00000000d7eeb000-0x00000000d7ffffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000d8000000-0x00000000d875ffff] usable [ 0.000000] BIOS-e820: [mem 0x00000000d8760000-0x00000000d87fffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000d8800000-0x00000000d8fadfff] usable [ 0.000000] BIOS-e820: [mem 0x00000000d8fae000-0x00000000d8ffffff] ACPI data [ 0.000000] BIOS-e820: [mem 0x00000000d9000000-0x00000000da71bfff] usable [ 0.000000] BIOS-e820: [mem 0x00000000da71c000-0x00000000da7fffff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000da800000-0x00000000dbb8bfff] usable [ 0.000000] BIOS-e820: [mem 0x00000000dbb8c000-0x00000000dbffffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000dd000000-0x00000000df1fffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000f8000000-0x00000000fbffffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fec00000-0x00000000fec00fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed00000-0x00000000fed03fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fee00000-0x00000000fee00fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000ff000000-0x00000000ffffffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000041edfffff] usable Fix this problem by changing pfn limit from max_low_pfn to max_pfn. This fix does not impact 64bit system because on 64bit max_low_pfn is the same as max_pfn. Signed-off-by: Zhimin Gu Acked-by: Pavel Machek Signed-off-by: Chen Yu Acked-by: Thomas Gleixner Cc: All applicable Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

x86/tsc: Force inlining of cyc2ns bits

2018-11-10T15:49:47+00:00

commit 4907c68abd3f60f650f98d5a69d4ec77c0bde44f upstream. Looking at the asm for native_sched_clock() I noticed we don't inline enough. Mostly caused by sharing code with cyc2ns_read_begin(), which we didn't used to do. So mark all that __force_inline to make it DTRT. Fixes: 59eaef78bfea ("x86/tsc: Remodel cyc2ns to use seqcount_latch()") Reported-by: Eric Dumazet Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: hpa@zytor.com Cc: eric.dumazet@gmail.com Cc: bp@alien8.de Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181011104019.695196158@infradead.org Signed-off-by: Greg Kroah-Hartman

sched/fair: Fix throttle_list starvation with low CFS quota

2018-11-10T15:49:47+00:00

commit baa9be4ffb55876923dc9716abc0a448e510ba30 upstream. With a very low cpu.cfs_quota_us setting, such as the minimum of 1000, distribute_cfs_runtime may not empty the throttled_list before it runs out of runtime to distribute. In that case, due to the change from c06f04c7048 to put throttled entries at the head of the list, later entries on the list will starve. Essentially, the same X processes will get pulled off the list, given CPU time and then, when expired, get put back on the head of the list where distribute_cfs_runtime will give runtime to the same set of processes leaving the rest. Fix the issue by setting a bit in struct cfs_bandwidth when distribute_cfs_runtime is running, so that the code in throttle_cfs_rq can decide to put the throttled entry on the tail or the head of the list. The bit is set/cleared by the callers of distribute_cfs_runtime while they hold cfs_bandwidth->lock. This is easy to reproduce with a handful of CPU consumers. I use 'crash' on the live system. In some cases you can simply look at the throttled list and see the later entries are not changing: crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1" "$4}' | pr -t -n3 1 ffff90b56cb2d200 -976050 2 ffff90b56cb2cc00 -484925 3 ffff90b56cb2bc00 -658814 4 ffff90b56cb2ba00 -275365 5 ffff90b166a45600 -135138 6 ffff90b56cb2da00 -282505 7 ffff90b56cb2e000 -148065 8 ffff90b56cb2fa00 -872591 9 ffff90b56cb2c000 -84687 10 ffff90b56cb2f000 -87237 11 ffff90b166a40a00 -164582 crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1" "$4}' | pr -t -n3 1 ffff90b56cb2d200 -994147 2 ffff90b56cb2cc00 -306051 3 ffff90b56cb2bc00 -961321 4 ffff90b56cb2ba00 -24490 5 ffff90b166a45600 -135138 6 ffff90b56cb2da00 -282505 7 ffff90b56cb2e000 -148065 8 ffff90b56cb2fa00 -872591 9 ffff90b56cb2c000 -84687 10 ffff90b56cb2f000 -87237 11 ffff90b166a40a00 -164582 Sometimes it is easier to see by finding a process getting starved and looking at the sched_info: crash> task ffff8eb765994500 sched_info PID: 7800 TASK: ffff8eb765994500 CPU: 16 COMMAND: "cputest" sched_info = { pcount = 8, run_delay = 697094208, last_arrival = 240260125039, last_queued = 240260327513 }, crash> task ffff8eb765994500 sched_info PID: 7800 TASK: ffff8eb765994500 CPU: 16 COMMAND: "cputest" sched_info = { pcount = 8, run_delay = 697094208, last_arrival = 240260125039, last_queued = 240260327513 }, Signed-off-by: Phil Auld Reviewed-by: Ben Segall Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org Fixes: c06f04c70489 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop") Link: http://lkml.kernel.org/r/20181008143639.GA4019@pauld.bos.csb Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

drm/sun4i: Fix an ulong overflow in the dotclock driver

2018-11-10T15:49:47+00:00

commit e84cb605e02f1b3d0aee8d7157419cd8aaa06038 upstream. The calculated ideal rate can easily overflow an unsigned long, thus making the best div selection buggy as soon as no ideal match is found before the overflow occurs. Fixes: 4731a72df273 ("drm/sun4i: request exact rates to our parents") Cc: Signed-off-by: Boris Brezillon Acked-by: Maxime Ripard Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20181018100250.12565-1-boris.brezillon@bootlin.com Signed-off-by: Greg Kroah-Hartman

Input: elan_i2c - add ACPI ID for Lenovo IdeaPad 330-15IGM

2018-11-10T15:49:47+00:00

commit 13c1c5e4d7f887cba36c5e3df3faa22071c1469f upstream. Add ELAN061C to the ACPI table to support Elan touchpad found in Lenovo IdeaPad 330-15IGM. Signed-off-by: Mikhail Nikiforov Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman