kernel/linux.git/include/linux, branch v4.9.218

locking/atomic, kref: Add kref_read()

2020-04-02T15:20:40+00:00

commit 2c935bc57221cc2edc787c72ea0e2d30cdcd3d5e upstream. Since we need to change the implementation, stop exposing internals. Provide kref_read() to read the current reference count; typically used for debug messages. Kills two anti-patterns: atomic_read(&kref->refcount) kref->refcount.counter Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Greg Kroah-Hartman Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar [only add kref_read() to kref.h for stable backports - gregkh] Signed-off-by: Greg Kroah-Hartman

vt: switch vt_dont_switch to bool

2020-04-02T15:20:39+00:00

commit f400991bf872debffb01c46da882dc97d7e3248e upstream. vt_dont_switch is pure boolean, no need for whole char. Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20200219073951.16151-6-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

vt: selection, introduce vc_is_sel

2020-04-02T15:20:39+00:00

commit dce05aa6eec977f1472abed95ccd71276b9a3864 upstream. Avoid global variables (namely sel_cons) by introducing vc_is_sel. It checks whether the parameter is the current selection console. This will help putting sel_cons to a struct later. Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20200219073951.16151-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

futex: Fix inode life-time issue

2020-04-02T15:20:27+00:00

commit 8019ad13ef7f64be44d4f892af9c840179009254 upstream. As reported by Jann, ihold() does not in fact guarantee inode persistence. And instead of making it so, replace the usage of inode pointers with a per boot, machine wide, unique inode identifier. This sequence number is global, but shared (file backed) futexes are rare enough that this should not become a performance issue. Reported-by: Jann Horn Suggested-by: Linus Torvalds Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Greg Kroah-Hartman

x86/mm: split vmalloc_sync_all()

2020-04-02T15:20:26+00:00

commit 763802b53a427ed3cbd419dbba255c414fdd9e7c upstream. Commit 3f8fd02b1bf1 ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in the vunmap() code-path. While this change was necessary to maintain correctness on x86-32-pae kernels, it also adds additional cycles for architectures that don't need it. Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported severe performance regressions in micro-benchmarks because it now also calls the x86-64 implementation of vmalloc_sync_all() on vunmap(). But the vmalloc_sync_all() implementation on x86-64 is only needed for newly created mappings. To avoid the unnecessary work on x86-64 and to gain the performance back, split up vmalloc_sync_all() into two functions: * vmalloc_sync_mappings(), and * vmalloc_sync_unmappings() Most call-sites to vmalloc_sync_all() only care about new mappings being synchronized. The only exception is the new call-site added in the above mentioned commit. Shile Zhang directed us to a report of an 80% regression in reaim throughput. Fixes: 3f8fd02b1bf1 ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") Reported-by: kernel test robot Reported-by: Shile Zhang Signed-off-by: Joerg Roedel Signed-off-by: Andrew Morton Tested-by: Borislav Petkov Acked-by: Rafael J. Wysocki [GHES] Cc: Dave Hansen Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/ Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

net: phy: fix MDIO bus PM PHY resuming

2020-03-20T08:07:43+00:00

[ Upstream commit 611d779af7cad2b87487ff58e4931a90c20b113c ] So far we have the unfortunate situation that mdio_bus_phy_may_suspend() is called in suspend AND resume path, assuming that function result is the same. After the original change this is no longer the case, resulting in broken resume as reported by Geert. To fix this call mdio_bus_phy_may_suspend() in the suspend path only, and let the phy_device store the info whether it was suspended by MDIO bus PM. Fixes: 503ba7c69610 ("net: phy: Avoid multiple suspends") Reported-by: Geert Uytterhoeven Tested-by: Geert Uytterhoeven Signed-off-by: Heiner Kallweit Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

include/linux/bitops.h: introduce BITS_PER_TYPE

2020-03-11T06:53:07+00:00

commit 9144d75e22cad3c89e6b2ccab551db9ee28d250a upstream. net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the macro to bitops.h, alongside BITS_PER_BYTE, for wider usage. Link: http://lkml.kernel.org/r/20180706094458.14116-1-chris@chris-wilson.co.uk Signed-off-by: Chris Wilson Reviewed-by: Jani Nikula Cc: Randy Dunlap Cc: Andy Gospodarek Cc: David S. Miller Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [only take the bitops.h portion for stable kernels - gregkh] Signed-off-by: Greg Kroah-Hartman

HID: core: increase HID report buffer size to 8KiB

2020-03-11T06:53:06+00:00

commit 84a4062632462c4320704fcdf8e99e89e94c0aba upstream. We have a HID touch device that reports its opens and shorts test results in HID buffers of size 8184 bytes. The maximum size of the HID buffer is currently set to 4096 bytes, causing probe of this device to fail. With this patch we increase the maximum size of the HID buffer to 8192 bytes, making device probe and acquisition of said buffers succeed. Signed-off-by: Johan Korsnes Cc: Alan Stern Cc: Armando Visconti Cc: Jiri Kosina Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman

ata: ahci: Add shutdown to freeze hardware resources of ahci

2020-02-28T14:42:56+00:00

commit 10a663a1b15134a5a714aa515e11425a44d4fdf7 upstream. device_shutdown() called from reboot or power_shutdown expect all devices to be shutdown. Same is true for even ahci pci driver. As no ahci shutdown function is implemented, the ata subsystem always remains alive with DMA & interrupt support. File system related calls should not be honored after device_shutdown(). So defining ahci pci driver shutdown to freeze hardware (mask interrupt, stop DMA engine and free DMA resources). Signed-off-by: Prabhakar Kushwaha Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

rcu: Use WRITE_ONCE() for assignments to ->pprev for hlist_nulls

2020-02-28T14:42:30+00:00

[ Upstream commit 860c8802ace14c646864795e057349c9fb2d60ad ] Eric Dumazet supplied a KCSAN report of a bug that forces use of hlist_unhashed_lockless() from sk_unhashed(): ------------------------------------------------------------------------ BUG: KCSAN: data-race in inet_unhash / inet_unhash write to 0xffff8880a69a0170 of 8 bytes by interrupt on cpu 1: __hlist_nulls_del include/linux/list_nulls.h:88 [inline] hlist_nulls_del_init_rcu include/linux/rculist_nulls.h:36 [inline] __sk_nulls_del_node_init_rcu include/net/sock.h:676 [inline] inet_unhash+0x38f/0x4a0 net/ipv4/inet_hashtables.c:612 tcp_set_state+0xfa/0x3e0 net/ipv4/tcp.c:2249 tcp_done+0x93/0x1e0 net/ipv4/tcp.c:3854 tcp_write_err+0x7e/0xc0 net/ipv4/tcp_timer.c:56 tcp_retransmit_timer+0x9b8/0x16d0 net/ipv4/tcp_timer.c:479 tcp_write_timer_handler+0x42d/0x510 net/ipv4/tcp_timer.c:599 tcp_write_timer+0xd1/0xf0 net/ipv4/tcp_timer.c:619 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71 arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 start_secondary+0x208/0x260 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 read to 0xffff8880a69a0170 of 8 bytes by interrupt on cpu 0: sk_unhashed include/net/sock.h:607 [inline] inet_unhash+0x3d/0x4a0 net/ipv4/inet_hashtables.c:592 tcp_set_state+0xfa/0x3e0 net/ipv4/tcp.c:2249 tcp_done+0x93/0x1e0 net/ipv4/tcp.c:3854 tcp_write_err+0x7e/0xc0 net/ipv4/tcp_timer.c:56 tcp_retransmit_timer+0x9b8/0x16d0 net/ipv4/tcp_timer.c:479 tcp_write_timer_handler+0x42d/0x510 net/ipv4/tcp_timer.c:599 tcp_write_timer+0xd1/0xf0 net/ipv4/tcp_timer.c:619 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71 arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 rest_init+0xec/0xf6 init/main.c:452 arch_call_rest_init+0x17/0x37 start_kernel+0x838/0x85e init/main.c:786 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc6+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ------------------------------------------------------------------------ This commit therefore replaces C-language assignments with WRITE_ONCE() in include/linux/list_nulls.h and include/linux/rculist_nulls.h. Reported-by: Eric Dumazet # For KCSAN Signed-off-by: Paul E. McKenney Signed-off-by: Sasha Levin