linux/arch/powerpc/kernel
Gustavo Romero 1c200e63d0 powerpc/tm: Fix endianness flip on trap
Currently it's possible that a thread on PPC64 LE has its endianness
flipped inadvertently to Big-Endian resulting in a crash once the process
is back from the signal handler.

If giveup_all() is called when regs->msr has the bits MSR.FP and MSR.VEC
disabled (and hence MSR.VSX disabled too) it returns without calling
check_if_tm_restore_required() which copies regs->msr to ckpt_regs->msr if
the process caught a signal whilst in transactional mode. Then once in
setup_tm_sigcontexts() MSR from ckpt_regs.msr is used, but since
check_if_tm_restore_required() was not called previuosly, gp_regs[PT_MSR]
gets a copy of invalid MSR bits as MSR in ckpt_regs was not updated from
regs->msr and so is zeroed. Later when leaving the signal handler once in
sys_rt_sigreturn() the TS bits of gp_regs[PT_MSR] are checked to determine
if restore_tm_sigcontexts() must be called to pull in the correct MSR state
into the user context. Because TS bits are zeroed
restore_tm_sigcontexts() is never called and MSR restored from the user
context on returning from the signal handler has the MSR.LE (the endianness
bit) forced to zero (Big-Endian). That leads, for instance, to 'nop' being
treated as an illegal instruction in the following sequence:

	tbegin.
	beq	1f
	trap
	tend.
1:	nop

on PPC64 LE machines and the process dies just after returning from the
signal handler.

PPC64 BE is also affected but in a subtle way since forcing Big-Endian on
a BE machine does not change the endianness.

This commit fixes the issue described above by ensuring that once in
setup_tm_sigcontexts() the MSR used is from regs->msr instead of from
ckpt_regs->msr and by ensuring that we pull in only the MSR.FP, MSR.VEC,
and MSR.VSX bits from ckpt_regs->msr.

The fix was tested both on LE and BE machines and no regression regarding
the powerpc/tm selftests was observed.

Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-22 05:48:36 +11:00
..
trace powerpc updates for 4.15 2017-11-16 12:47:46 -08:00
vdso32 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vdso64 powerpc/vdso64: Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE 2017-12-04 15:01:09 +11:00
.gitignore
align.c powerpc: Fix check for copy/paste instructions in alignment handler 2017-10-25 12:42:35 +02:00
asm-offsets.c Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
btext.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cacheinfo.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
cacheinfo.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compat_audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cpu_setup_6xx.S powerpc: Various typo fixes 2016-06-14 13:58:26 +10:00
cpu_setup_44x.S
cpu_setup_fsl_booke.S powerpc/cache: add cache flush operation for various e500 2016-03-04 23:44:51 -06:00
cpu_setup_pa6t.S
cpu_setup_power.S Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
cpu_setup_ppc970.S
cputable.c powerpc/64s: Improve local TLB flush for boot and MCE on POWER9 2018-01-18 00:40:31 +11:00
crash_dump.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
crash.c powernv/kdump: Fix cases where the kdump kernel can get HMI's 2018-01-16 23:47:11 +11:00
dbell.c powerpc: Introduce msgsnd/doorbell barrier primitives 2017-04-13 23:34:33 +10:00
dma-iommu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dma-swiotlb.c treewide: Constify most dma_map_ops structures 2017-01-24 12:23:35 -05:00
dma.c powerpc: merge __dma_set_mask into dma_set_mask 2017-06-28 06:54:55 -07:00
dt_cpu_ftrs.c powerpc/64s: Improve local TLB flush for boot and MCE on POWER9 2018-01-18 00:40:31 +11:00
eeh_cache.c powerpc/eeh: Fix pr_debug()s in eeh_cache.c 2016-07-08 22:09:50 +10:00
eeh_dev.c powerpc/eeh: Create PHB PEs after EEH is initialized 2017-09-21 14:56:00 +10:00
eeh_driver.c powerpc/pci: Separate SR-IOV Calls 2017-12-11 13:03:35 +11:00
eeh_event.c powerpc/pci: Always print PHB and PE numbers as hexadecimal 2016-11-22 11:57:07 +11:00
eeh_pe.c powerpc/eeh: Stop using do_gettimeofday() 2017-11-06 17:40:00 +11:00
eeh_sysfs.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
eeh.c powerpc/powernv: Rework EEH initialization on powernv 2017-09-26 11:19:07 +10:00
entry_32.S powerpc/8xx: Only perform perf counting when perf is in use. 2018-01-16 23:47:12 +11:00
entry_64.S Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
epapr_hcalls.S ppc: move exports to definitions 2016-08-07 23:50:09 -04:00
epapr_paravirt.c
exceptions-64e.S powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
exceptions-64s.S Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
fadump.c Revert "powerpc: Do not call ppc_md.panic in fadump panic notifier" 2017-12-05 23:21:46 +11:00
firmware.c
fpu.S Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-10-14 14:26:58 -07:00
fsl_booke_entry_mapping.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head_8xx.S powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP 2018-01-16 23:47:15 +11:00
head_32.S powerpc: Fix DABR match on hash based systems 2017-11-13 22:12:48 +11:00
head_40x.S ppc: move exports to definitions 2016-08-07 23:50:09 -04:00
head_44x.S ppc: move exports to definitions 2016-08-07 23:50:09 -04:00
head_64.S powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
head_booke.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head_fsl_booke.S ppc: move exports to definitions 2016-08-07 23:50:09 -04:00
hw_breakpoint.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next 2017-02-18 21:37:14 +11:00
idle_6xx.S
idle_book3e.S powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
idle_book3s.S powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature 2017-11-15 14:25:42 +11:00
idle_e500.S
idle_power4.S powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
idle.c
ima_kexec.c powerpc: ima: send the kexec buffer to the next kernel 2016-12-20 09:48:44 -08:00
io-workarounds.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
io.c
iomap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
iommu.c powerpc/iommu: Use permission-specific DEVICE_ATTR variants 2017-09-01 16:42:54 +10:00
irq.c powerpc: Add new kconfig CONFIG_PPC_IRQ_SOFT_MASK_DEBUG 2018-01-19 22:37:03 +11:00
isa-bridge.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
jump_label.c
kexec_elf_64.c powerpc: ima: send the kexec buffer to the next kernel 2016-12-20 09:48:44 -08:00
kgdb.c powerpc/8xx: Getting rid of remaining use of CONFIG_8xx 2017-08-10 23:32:12 +10:00
kprobes-ftrace.c powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace 2017-11-12 23:51:41 +11:00
kprobes.c powerpc/kprobes: refactor kprobe_lookup_name for safer string operations 2017-11-12 23:51:43 +11:00
kvm_emul.S
kvm.c powerpc/64: Fix watchdog configuration regressions 2017-08-31 14:26:00 +10:00
l2cr_6xx.S powerpc/l2cr_6xx: Fix invalid use of register expressions 2017-08-15 21:04:32 +10:00
legacy_serial.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
machine_kexec_32.c
machine_kexec_64.c powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64 2017-11-06 16:48:14 +11:00
machine_kexec_file_64.c resource: Provide resource struct in resource walk callback 2017-11-07 15:35:57 +01:00
machine_kexec.c powerpc: Update of_remove_property() call sites to remove null checking 2016-05-11 21:54:04 +10:00
Makefile powerpc updates for 4.15 2017-11-16 12:47:46 -08:00
mce_power.c powerpc/64s: Improve local TLB flush for boot and MCE on POWER9 2018-01-18 00:40:31 +11:00
mce.c KVM: PPC: Book3S HV: Improve handling of debug-trigger HMIs on POWER9 2018-01-18 15:31:25 +11:00
misc_32.S powerpc/40x: Clear MSR_DR in one insn instead of two 2017-06-02 19:20:43 +10:00
misc_64.S powerpc/kexec: Fix kexec/kdump in P9 guest kernels 2017-11-24 16:49:37 +11:00
misc.S ppc: move exports to definitions 2016-08-07 23:50:09 -04:00
module_32.c powerpc/module: Only try to generate the ftrace_caller() stub once 2016-03-07 14:53:53 +11:00
module_64.c powerpc/modules: Fix alignment of .toc section in kernel modules 2017-12-11 13:03:35 +11:00
module.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
module.lds powerpc/modules: Fix alignment of .toc section in kernel modules 2017-12-11 13:03:35 +11:00
msi.c
nvram_64.c powerpc/nvram: use memdup_user 2017-06-27 17:02:50 -07:00
of_platform.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
optprobes_head.S powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
optprobes.c powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace 2017-11-12 23:51:41 +11:00
paca.c powerpc/64s: Relax PACA address limitations 2018-01-18 15:42:48 +11:00
pci_32.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
pci_64.c powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64 2017-11-06 16:48:14 +11:00
pci_dn.c powerpc/pci: Separate SR-IOV Calls 2017-12-11 13:03:35 +11:00
pci_of_scan.c powerpc: Convert to using %pOF instead of full_name 2017-08-23 22:27:04 +10:00
pci-common.c powerpc/pci: Separate SR-IOV Calls 2017-12-11 13:03:35 +11:00
pci-hotplug.c powerpc/pci: Don't scan empty slot 2016-05-11 21:54:26 +10:00
pmc.c
ppc32.h
ppc_save_regs.S
proc_powerpc.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
process.c Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
prom_init_check.sh
prom_init.c powerpc: Enable support for ibm,drc-info devtree property 2018-01-21 16:21:50 +11:00
prom_parse.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
prom.c powerpc/mm: Separate ibm, dynamic-memory data from DT format 2018-01-16 23:26:27 +11:00
ptrace32.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ptrace.c powerpc/ptrace: Add memory protection key regset 2018-01-20 22:59:06 +11:00
reloc_32.S
reloc_64.S powerpc/asm: Convert .llong directives to .8byte 2017-08-31 14:26:47 +10:00
rtas_flash.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
rtas_pci.c powerpc/kernel: Change retrieval of pci_dn 2017-08-31 14:26:40 +10:00
rtas-proc.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
rtas-rtc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rtas.c locking/arch, powerpc/rtas: Use arch_spin_lock() instead of arch_spin_lock_flags() 2017-10-18 15:15:07 +02:00
rtasd.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
setup_32.c powerpc/32: remove a NOP from memset() 2017-09-01 16:42:46 +10:00
setup_64.c Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
setup-common.c Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
setup.h powerpc/64s: Relax PACA address limitations 2018-01-18 15:42:48 +11:00
signal_32.c powerpc: Hard wire PT_SOFTE value to 1 in ptrace & signals 2018-01-19 22:36:54 +11:00
signal_64.c powerpc/tm: Fix endianness flip on trap 2018-01-22 05:48:36 +11:00
signal.c powerpc/signal: Properly handle return value from uprobe_deny_signal() 2017-11-13 10:53:05 +11:00
signal.h powerpc: tm: Rename transct_(*) to ck(\1)_state 2016-10-04 20:33:16 +11:00
smp-tbsync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
smp.c powernv/kdump: Fix cases where the kdump kernel can get HMI's 2018-01-16 23:47:11 +11:00
stacktrace.c powerpc: Make /proc/self/stack always print the current stack 2017-03-28 14:43:59 +11:00
suspend.c
swsusp_32.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swsusp_64.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/nmi.h> 2017-03-02 08:42:30 +01:00
swsusp_asm64.S powerpc: Fix invalid use of register expressions 2017-08-10 22:29:41 +10:00
swsusp_booke.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swsusp.c powerpc/swsusp: Include suspend.h to silence sparse warnings 2017-03-20 19:02:49 +11:00
sys_ppc32.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
syscalls.c powerpc/tracing: Allow tracing of mmap syscalls 2017-04-12 22:32:43 +10:00
sysfs.c powerpc: Expose TSCR via sysfs 2018-01-22 05:48:36 +11:00
systbl_chk.c powerpc: Standardise on NR_syscalls rather than __NR_syscalls. 2015-11-26 22:11:17 +11:00
systbl_chk.sh powerpc: Standardise on NR_syscalls rather than __NR_syscalls. 2015-11-26 22:11:17 +11:00
systbl.S powerpc/asm: Convert .llong directives to .8byte 2017-08-31 14:26:47 +10:00
tau_6xx.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
time.c powerpc/64: Rename soft_enabled to irq_soft_mask 2018-01-19 22:37:01 +11:00
tm.S powerpc updates for 4.15 2017-11-16 12:47:46 -08:00
traps.c powerpc: Use octal numbers for file permissions 2018-01-22 05:48:33 +11:00
udbg_16550.c
udbg.c
uprobes.c powerpc/uprobes: Implement arch_uretprobe_is_alive() 2017-08-24 16:19:21 +10:00
vdso.c powerpc/64: Clean up ppc64_caches using a struct per cache 2017-02-06 19:46:04 +11:00
vecemu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vector.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vmlinux.lds.S Merge branch 'fixes' into next 2018-01-21 23:21:14 +11:00
watchdog.c powerpc/watchdog: improve watchdog comments 2018-01-21 15:06:26 +11:00