linux_dsm_epyc7002/arch/powerpc/kernel
Michael Ellerman 912c0a7f2b powerpc/64s: Save FSCR to init_task.thread.fscr after feature init
At boot the FSCR is initialised via one of two paths. On most systems
it's set to a hard coded value in __init_FSCR().

On newer skiboot systems we use the device tree CPU features binding,
where firmware can tell Linux what bits to set in FSCR (and HFSCR).

In both cases the value that's configured at boot is not propagated
into the init_task.thread.fscr value prior to the initial fork of init
(pid 1), which means the value is not used by any processes other than
swapper (the idle task).

For the __init_FSCR() case this is OK, because the value in
init_task.thread.fscr is initialised to something sensible. However it
does mean that the value set in __init_FSCR() is not used other than
for swapper, which is odd and confusing.

The bigger problem is for the device tree CPU features case it
prevents firmware from setting (or clearing) FSCR bits for use by user
space. This means all existing kernels can not have features
enabled/disabled by firmware if those features require
setting/clearing FSCR bits.

We can handle both cases by saving the FSCR value into
init_task.thread.fscr after we have initialised it at boot. This fixes
the bug for device tree CPU features, and will allow us to simplify
the initialisation for the __init_FSCR() case in a future patch.

Fixes: 5a61ef74f2 ("powerpc/64s: Support new device tree binding for discovering CPU features")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527145843.2761782-3-mpe@ellerman.id.au
2020-06-02 20:59:18 +10:00
..
ptrace powerpc/watchpoint: Use builtin ALIGN*() macros 2020-05-19 00:11:05 +10:00
syscalls asm-generic: fix unistd_32.h generation format 2020-04-07 10:43:42 -07:00
trace powerpc: Add a probe_kernel_read_inst() function 2020-05-19 00:10:37 +10:00
vdso32 powerpc/vdso32: Fallback on getres syscall when clock is unknown 2020-05-11 19:24:29 +10:00
vdso64 .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
align.c powerpc: Define and use get_user_instr() et. al. 2020-05-19 00:10:37 +10:00
asm-offsets.c powerpc/xmon: Move breakpoints to text section 2020-05-19 00:10:36 +10:00
audit.c
btext.c powerpc: Prefer __section and __printf from compiler_attributes.h 2020-03-27 00:16:32 +11:00
cacheinfo.c powerpc updates for 5.3 2019-07-13 16:08:36 -07:00
cacheinfo.h
compat_audit.c
cpu_setup_6xx.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
cpu_setup_44x.S
cpu_setup_fsl_booke.S powerpc/booke: Spelling s/date/data/ 2019-11-17 01:56:31 -06:00
cpu_setup_pa6t.S
cpu_setup_power.S powerpc/64s: Don't init FSCR_DSCR in __init_FSCR() 2020-06-02 20:59:17 +10:00
cpu_setup_ppc970.S
cputable.c powerpc/40x: Remove support for IBM 405GP 2020-05-28 23:24:36 +10:00
crash_dump.c powerpc: Add prefixed instructions to instruction data type 2020-05-19 00:10:39 +10:00
dawr.c powerpc/watchpoint: Disable all available watchpoints when !dawr_force_enable 2020-05-19 00:11:05 +10:00
dbell.c KVM: PPC: Book3S HV: use smp_mb() when setting/clearing host_ipi flag 2019-09-24 12:46:26 +10:00
dma-iommu.c powerpc updates for 5.4 2019-09-20 11:48:06 -07:00
dma-mask.c
dma-swiotlb.c
dt_cpu_ftrs.c powerpc/64s: Don't let DT CPU features set FSCR_DSCR 2020-06-02 20:59:17 +10:00
early_32.c powerpc/fsl_booke/32: implement KASLR infrastructure 2019-11-13 19:27:40 +11:00
eeh_cache.c powerpc/eeh_cache: Don't use pci_dn when inserting new ranges 2020-01-23 21:31:18 +11:00
eeh_dev.c powerpc/eeh: Add bdfn field to eeh_dev 2019-08-22 23:12:46 +10:00
eeh_driver.c powerpc/eeh: Fix deadlock handling dead PHB 2020-02-17 12:47:05 +11:00
eeh_event.c powerpc/eeh: Fix build with STACKTRACE=n 2019-09-14 00:01:14 +10:00
eeh_pe.c powerpc/eeh: Clean up EEH PEs after recovery finishes 2019-09-05 14:22:37 +10:00
eeh_sysfs.c powerpc/eeh_sysfs: Make clearing EEH_DEV_SYSFS saner 2020-01-23 21:31:19 +11:00
eeh.c powerpc/eeh: Release EEH device state synchronously 2020-05-18 21:58:44 +10:00
entry_32.S powerpc/entry32: Blacklist exception exit points for kprobe. 2020-06-02 20:59:13 +10:00
entry_64.S powerpc/64s/kuap: Conditionally restore AMR in kuap_restore_amr asm 2020-05-28 23:24:37 +10:00
epapr_hcalls.S
epapr_paravirt.c powerpc: Use a datatype for instructions 2020-05-19 00:10:37 +10:00
exceptions-64e.S powerpc/64s: Implement interrupt exit logic in C 2020-04-01 13:42:14 +11:00
exceptions-64s.S powerpc/64s/kuap: Conditionally restore AMR in kuap_restore_amr asm 2020-05-28 23:24:37 +10:00
fadump.c powerpc/fadump: Account for memory_limit while reserving memory 2020-06-02 20:59:05 +10:00
firmware.c
fpu.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
fsl_booke_entry_mapping.S powerpc/fsl_booke/32: implement KASLR infrastructure 2019-11-13 19:27:40 +11:00
head_8xx.S powerpc/8xx: Map linear memory with huge pages 2020-05-26 22:22:23 +10:00
head_32.h Merge branch 'fixes' into next 2020-03-10 15:16:42 +11:00
head_32.S powerpc/rtas: Remove machine_check_in_rtas() 2020-06-02 20:59:11 +10:00
head_40x.S powerpc/40x: Don't save CR in SPRN_SPRG_SCRATCH6 2020-05-28 23:24:36 +10:00
head_44x.S
head_64.S powerpc/64: Don't initialise init_task->thread.regs 2020-05-15 11:58:54 +10:00
head_booke.h powerpc: Replace _ALIGN_UP() by ALIGN() 2020-05-11 23:15:15 +10:00
head_fsl_booke.S powerpc/32: save DEAR/DAR before calling handle_page_fault 2020-01-26 22:15:09 +11:00
hw_breakpoint.c powerpc/watchpoint: Don't allow concurrent perf and ptrace events 2020-05-19 00:14:45 +10:00
idle_6xx.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
idle_book3e.S
idle_book3s.S powerpc/64s: Reimplement power4_idle code in C 2020-01-16 14:59:37 +10:00
idle_e500.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
idle.c powerpc/64s: Reimplement power4_idle code in C 2020-01-16 14:59:37 +10:00
ima_arch.c powerpc/ima: Fix secure boot rules in ima arch policy 2020-05-07 17:25:54 +10:00
io-workarounds.c powerpc/mm: rework io-workaround invocation. 2019-08-27 13:03:34 +10:00
io.c
iomap.c
iommu.c Merge branch 'topic/ppc-kvm' into next 2019-08-30 09:52:57 +10:00
irq.c powerpc/64s: Fix doorbell wakeup msgclr optimisation 2020-04-03 00:09:53 +11:00
isa-bridge.c
jump_label.c powerpc: Use a datatype for instructions 2020-05-19 00:10:37 +10:00
kgdb.c powerpc: Use a datatype for instructions 2020-05-19 00:10:37 +10:00
kprobes-ftrace.c
kprobes.c powerpc/kprobes: Use probe_address() to read instructions 2020-06-02 20:59:08 +10:00
kvm_emul.S powerpc/kvm: Add ifdefs around template code 2019-09-14 00:04:40 +10:00
kvm.c powerpc/kvm: Explicitly mark kvm guest code as __init 2019-09-14 00:04:40 +10:00
l2cr_6xx.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
legacy_serial.c tty/serial: Migrate 8250_fsl to use has_sysrq 2019-12-18 15:04:42 +01:00
Makefile powerpc/64: make buildable without CONFIG_COMPAT 2020-04-03 00:10:00 +11:00
mce_power.c powerpc: Use a function for reading instructions 2020-05-19 00:10:37 +10:00
mce.c powerpc/64s: machine check do not trace real-mode handler 2020-05-19 00:10:34 +10:00
misc_32.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
misc_64.S Merge branch 'topic/kaslr-book3e32' into next 2019-11-14 19:23:33 +11:00
misc.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
module_32.c powerpc: module_[32|64].c: replace swap function with built-in one 2020-05-11 23:15:14 +10:00
module_64.c powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel 2020-06-02 20:59:16 +10:00
module.c
module.lds
msi.c
note.S powerpc: Add PowerPC Capabilities ELF note 2019-08-30 09:40:15 +10:00
nvram_64.c powerpc: Replace _ALIGN_UP() by ALIGN() 2020-05-11 23:15:15 +10:00
of_platform.c powerpc/eeh: Make early EEH init pseries specific 2020-03-25 12:09:39 +11:00
optprobes_head.S powerpc: Add prefixed instructions to instruction data type 2020-05-19 00:10:39 +10:00
optprobes.c powerpc: Add ppc_inst_as_u64() 2020-05-26 23:36:57 +10:00
paca.c powerpc/rtas: Implement reentrant rtas call 2020-06-02 20:59:08 +10:00
pci_32.c powerpc/64: Adjust order in pcibios_init() 2019-08-22 23:11:48 +10:00
pci_64.c powerpc: Replace _ALIGN_UP() by ALIGN() 2020-05-11 23:15:15 +10:00
pci_dn.c powerpc/pcidn: Warn when sriov pci_dn management is used incorrectly 2020-01-23 21:31:19 +11:00
pci_of_scan.c powerpc/pci: Remove pcibios_setup_bus_devices() 2020-01-06 16:25:29 +11:00
pci-common.c powerpc updates for 5.7 2020-04-05 11:12:59 -07:00
pci-hotplug.c powerpc/eeh: Release EEH device state synchronously 2020-05-18 21:58:44 +10:00
pmc.c
ppc32.h
ppc_save_regs.S powerpc: Improve ppc_save_regs() 2020-04-04 21:40:57 +11:00
proc_powerpc.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
process.c powerpc/watchpoint: Prepare handler to handle more than one watchpoint 2020-05-19 00:14:37 +10:00
prom_init_check.sh powerpc/prom_init: Undo relocation before entering secure mode 2019-10-29 15:12:17 +11:00
prom_init.c powerpc: Replace _ALIGN() by ALIGN() 2020-05-11 23:15:16 +10:00
prom_parse.c
prom.c powerpc/64s: Save FSCR to init_task.thread.fscr after feature init 2020-06-02 20:59:18 +10:00
reloc_32.S
reloc_64.S
rtas_flash.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
rtas_pci.c
rtas-proc.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
rtas-rtc.c
rtas.c powerpc/rtas: Implement reentrant rtas call 2020-06-02 20:59:08 +10:00
rtasd.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
secure_boot.c powerpc: Detect the trusted boot state of the system 2019-11-12 12:25:49 +11:00
security.c powerpc: Use a macro for creating instructions from u32s 2020-05-19 00:10:36 +10:00
secvar-ops.c powerpc/powernv: Add OPAL API interface to access secure variable 2019-11-13 00:33:22 +11:00
secvar-sysfs.c powerpc: expose secure variables to userspace via sysfs 2019-11-13 00:33:22 +11:00
setup_32.c powerpc/mm: Allocate static page tables for fixmap 2020-05-26 22:22:19 +10:00
setup_64.c Merge branch 'fixes' into next 2020-05-26 22:56:03 +10:00
setup-common.c powerpc/40x: Remove support for IBM 403GCX 2020-05-28 23:24:35 +10:00
setup.h powerpc/64: Prevent stack protection in early boot 2020-03-25 12:09:38 +11:00
signal_32.c powerpc: Use trap metadata to prevent double restart rather than zeroing trap 2020-05-15 11:58:54 +10:00
signal_64.c powerpc: Use trap metadata to prevent double restart rather than zeroing trap 2020-05-15 11:58:54 +10:00
signal.c powerpc/watchpoint: Convert thread_struct->hw_brk to an array 2020-05-19 00:11:05 +10:00
signal.h powerpc/64/sycall: Implement syscall entry/exit logic in C 2020-04-01 13:42:13 +11:00
smp-tbsync.c
smp.c powerpc: Fix misleading small cores print 2020-06-02 20:59:06 +10:00
stacktrace.c powerpc: Rename current_stack_pointer() to current_stack_frame() 2020-03-04 22:44:28 +11:00
suspend.c
swsusp_32.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
swsusp_64.c
swsusp_asm64.S
swsusp_booke.S
swsusp.c
sys_ppc32.c
syscall_64.c powerpc/64/kuap: Conditionally restore AMR in interrupt exit 2020-05-28 23:24:37 +10:00
syscalls.c y2038: syscalls: change remaining timeval to __kernel_old_timeval 2019-11-15 14:38:29 +01:00
sysfs.c powerpc/sysfs: Show idle_purr and idle_spurr for every CPU 2020-04-30 12:35:26 +10:00
systbl_chk.sh
systbl.S powerpc/64/sycall: Implement syscall entry/exit logic in C 2020-04-01 13:42:13 +11:00
tau_6xx.c
time.c Revert "powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled" 2020-04-03 16:55:34 +11:00
tm.S
traps.c powerpc: Support prefixed instructions in alignment handler 2020-05-19 00:11:03 +10:00
ucall.S powerpc/kernel: Add ucall_norets() ultravisor call handler 2019-08-30 09:40:15 +10:00
udbg_16550.c
udbg.c powerpc/udbg: Make it safe to call udbg_printf() always 2019-10-11 19:33:25 +11:00
uprobes.c powerpc: Add ppc_inst_next() 2020-05-26 23:36:51 +10:00
vdso.c powerpc/64: make buildable without CONFIG_COMPAT 2020-04-03 00:10:00 +11:00
vecemu.c powerpc: Define and use get_user_instr() et. al. 2020-05-19 00:10:37 +10:00
vector.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
vmlinux.lds.S powerpc/mm: Don't be too strict with _etext alignment on PPC32 2020-05-26 22:22:22 +10:00
watchdog.c