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linux-sg2042/drivers
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Breno Leitao 2b038cbc5f powerpc/pseries/cpuidle: Fix preempt warning 
When booting a pseries kernel with PREEMPT enabled, it dumps the
following warning:

   BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
   caller is pseries_processor_idle_init+0x5c/0x22c
   CPU: 13 PID: 1 Comm: swapper/0 Not tainted 4.20.0-rc3-00090-g12201a0128bc-dirty #828
   Call Trace:
   [c000000429437ab0] [c0000000009c8878] dump_stack+0xec/0x164 (unreliable)
   [c000000429437b00] [c0000000005f2f24] check_preemption_disabled+0x154/0x160
   [c000000429437b90] [c000000000cab8e8] pseries_processor_idle_init+0x5c/0x22c
   [c000000429437c10] [c000000000010ed4] do_one_initcall+0x64/0x300
   [c000000429437ce0] [c000000000c54500] kernel_init_freeable+0x3f0/0x500
   [c000000429437db0] [c0000000000112dc] kernel_init+0x2c/0x160
   [c000000429437e20] [c00000000000c1d0] ret_from_kernel_thread+0x5c/0x6c

This happens because the code calls get_lppaca() which calls
get_paca() and it checks if preemption is disabled through
check_preemption_disabled().

Preemption should be disabled because the per CPU variable may make no
sense if there is a preemption (and a CPU switch) after it reads the
per CPU data and when it is used.

In this device driver specifically, it is not a problem, because this
code just needs to have access to one lppaca struct, and it does not
matter if it is the current per CPU lppaca struct or not (i.e. when
there is a preemption and a CPU migration).

That said, the most appropriate fix seems to be related to avoiding
the debug_smp_processor_id() call at get_paca(), instead of calling
preempt_disable() before get_paca().

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
 		2018-12-04 19:45:01 +11:00
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accessibility
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acpi acpi/nfit, x86/mce: Validate a MCE's address before using it 2018-11-06 19:13:26 +01:00
amba
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android
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ata sata_rcar: convert to SPDX identifiers 2018-11-08 06:32:16 -07:00
atm atm: zatm: Fix empty body Clang warnings 2018-10-18 15:39:10 -07:00
auxdisplay The Compiler Attributes series 2018-11-01 18:34:46 -07:00
base mm/memory_hotplug: fix online/offline_pages called w.o. mem_hotplug_lock 2018-10-31 08:54:17 -07:00
bcma
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block xen: fixes for 4.20-rc2 2018-11-10 08:58:48 -06:00
bluetooth Merge branch 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-10-24 14:43:41 +01:00
bus ARM: SoC driver updates for 4.17 2018-10-29 15:16:01 -07:00
cdrom gdrom: fix mistake in assignment of error 2018-10-25 11:17:40 -06:00
char RTC for 4.20 2018-10-27 09:24:24 -07:00
clk clk: qcom: gcc: Fix board clock node name 2018-11-09 14:13:55 -08:00
clocksource Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-11 16:41:50 -06:00
connector
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cpufreq drivers/cpufreq: change CONFIG_6xx to CONFIG_PPC_BOOK3S_32 2018-11-26 22:33:37 +11:00
cpuidle powerpc/pseries/cpuidle: Fix preempt warning 2018-12-04 19:45:01 +11:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-10-25 16:43:35 -07:00
dax
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dca
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devfreq
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dio
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dma pci-v4.20-changes 2018-10-25 06:50:48 -07:00
dma-buf
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edac * skx_edac: Address translation for NVDIMMs (Tony Luck and Qiuxu Zhuo) 2018-11-02 11:17:22 -07:00
eisa
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extcon
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firewire
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firmware Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:25:17 -07:00
fmc
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fpga fpga: add devm_fpga_region_create 2018-10-16 11:13:50 +02:00
fsi iov_iter: Separate type from direction and use accessor functions 2018-10-24 00:41:07 +01:00
gnss
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gpio pci-v4.20-changes 2018-10-25 06:50:48 -07:00
gpu drm: i915, amdgpu, sun4i, exynos and etnaviv fixes 2018-11-10 13:29:47 -06:00
hid HID: asus: fix build warning wiht CONFIG_ASUS_WMI disabled 2018-11-06 13:57:42 +01:00
hsi
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hv hv_balloon: Replace spin_is_locked() with lockdep 2018-10-15 20:54:17 +02:00
hwmon hwmon: (ibmpowernv) Remove bogus __init annotations 2018-11-04 15:55:12 -08:00
hwspinlock
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hwtracing stm class: Use memcat_p() 2018-10-11 12:12:55 +02:00
i2c i2c: nvidia-gpu: make pm_ops static 2018-11-09 17:56:44 +01:00
ide
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idle Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 13:32:18 +01:00
iio Staging/IIO patches for 4.20-rc1 2018-10-29 10:38:10 -07:00
infiniband Revert "mm, mmu_notifier: annotate mmu notifiers with blockable invalidate callbacks" 2018-10-26 16:25:19 -07:00
input Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
iommu mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
ipack
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irqchip irqchip/irq-mvebu-sei: Fix a NULL vs IS_ERR() bug in probe function 2018-11-01 12:38:48 +01:00
isdn Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
leds LED fixes for 4.20-rc2 2018-11-08 17:49:04 -06:00
lightnvm
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macintosh macintosh: Use device_type helpers to access the node type 2018-11-26 22:33:37 +11:00
mailbox - Convert print users to use the %pOFn format specifier 2018-10-29 10:30:44 -07:00
mcb
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md for-linus-20181102 2018-11-02 11:25:48 -07:00
media media updates for v4.20-rc1 2018-10-31 10:53:29 -07:00
memory
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memstick
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message
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mfd chrome-platform for v4.20 2018-10-31 16:47:55 -07:00
misc cxl: Use device_type helpers to access the node type 2018-11-26 22:33:37 +11:00
mmc Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 13:32:18 +01:00
mtd mtd: sa1100: avoid VLA in sa1100_setup_mtd 2018-11-06 10:38:17 +01:00
mux This is the bulk of GPIO changes for the v4.20 series: 2018-10-23 08:45:05 +01:00
net net: dsa: mv88e6xxx: Fix clearing of stats counters 2018-11-11 10:19:10 -08:00
nfc NFC: nfcmrvl_uart: fix OF child-node lookup 2018-10-23 13:28:53 -05:00
ntb ntb: idt: Alter the driver info comments 2018-11-01 10:33:12 -04:00
nubus
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nvdimm libnvdimm for 4.20 2018-10-25 06:31:56 -07:00
nvme for-linus-20181109 2018-11-09 16:31:51 -06:00
nvmem nvmem: hide unused nvmem_find_cell_by_index function 2018-10-15 15:56:15 +02:00
of Devicetree fixes for 4.20-rc: 2018-11-09 16:41:58 -06:00
opp
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oprofile
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parisc parisc: Add alternative coding infrastructure 2018-10-17 17:22:26 +02:00
parport
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pci Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
pcmcia powerpc updates for 4.20 2018-10-26 14:36:21 -07:00
perf arm64 updates for 4.20: 2018-10-22 17:30:06 +01:00
phy USB/PHY patches for 4.20-rc1 2018-10-26 08:14:13 -07:00
pinctrl This is the bulk of GPIO changes for the v4.20 series: 2018-10-23 08:45:05 +01:00
platform platform-drivers-x86 for v4.20-1 2018-11-01 08:42:21 -07:00
pnp
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power Devicetree updates for 4.20: 2018-10-26 12:09:58 -07:00
powercap Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 13:32:18 +01:00
pps
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ps3
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ptp ptp: drop redundant kasprintf() to create worker name 2018-10-28 19:20:06 -07:00
pwm pwm: lpss: Only set update bit if we are actually changing the settings 2018-10-16 13:16:15 +02:00
rapidio
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ras
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regulator regulator: Regulator updates for next release 2018-10-23 01:54:44 +01:00
remoteproc remoteproc: qcom: q6v5-mss: Register segments/dumpfn for coredump 2018-10-19 12:54:03 -07:00
reset ARM: SoC driver updates for 4.17 2018-10-29 15:16:01 -07:00
rpmsg
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rtc rtc: sc27xx: Always read normal alarm when registering RTC device 2018-10-25 02:35:42 +02:00
s390 s390/qeth: report 25Gbit link speed 2018-11-03 10:44:06 -07:00
sbus
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scsi Kbuild updates for v4.20 (2nd) 2018-11-03 10:47:33 -07:00
sfi mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
sh
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siox
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slimbus
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sn
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soc soc: ti: QMSS: Fix usage of irq_set_affinity_hint 2018-11-02 11:22:09 -07:00
soundwire
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spi - New Drivers 2018-10-25 06:19:15 -07:00
spmi
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ssb
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staging media updates for v4.20-rc1 2018-10-31 10:53:29 -07:00
target SCSI misc on 20181102 2018-11-03 10:34:03 -07:00
tc TC: Set DMA masks for devices 2018-10-11 09:16:44 -07:00
tee
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thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2018-10-31 11:28:12 -07:00
thunderbolt
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tty TTY/Serial fixes for 4.20-rc2 2018-11-10 13:32:14 -06:00
uio
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usb usb: typec: ucsi: add support for Cypress CCGx 2018-11-09 18:49:59 +01:00
uwb
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vfio VFIO updates for v4.20 2018-10-31 11:01:38 -07:00
vhost virtio, vhost: fixes, tweaks 2018-11-01 14:42:49 -07:00
video fbdev changes for v4.20: 2018-10-31 11:41:37 -07:00
virt
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virtio virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON 2018-10-24 20:57:55 -04:00
visorbus
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vlynq
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vme
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w1 w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size). 2018-10-15 20:50:32 +02:00
watchdog watchdog: ts4800: release syscon device node in ts4800_wdt_probe() 2018-10-22 10:16:28 +02:00
xen xen: fixes for 4.20-rc2 2018-11-10 08:58:48 -06:00
zorro
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Kconfig
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Makefile
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