Commit graph

6562 commits

Author SHA1 Message Date
Nicholas Piggin
36d632ea83 powerpc/64: remove start_tb and accum_tb from thread_struct
These fields are only written to.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:26 +10:00
Nicholas Piggin
ebb37cf3ff powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled
irq_work_raise should not cause a decrementer exception unless it is
called from NMI context. Doing so often just results in an immediate
masked decrementer interrupt:

   <...>-550    90d...    4us : update_curr_rt <-dequeue_task_rt
   <...>-550    90d...    5us : dbs_update_util_handler <-update_curr_rt
   <...>-550    90d...    6us : arch_irq_work_raise <-irq_work_queue
   <...>-550    90d...    7us : soft_nmi_interrupt <-soft_nmi_common
   <...>-550    90d...    7us : printk_nmi_enter <-soft_nmi_interrupt
   <...>-550    90d.Z.    8us : rcu_nmi_enter <-soft_nmi_interrupt
   <...>-550    90d.Z.    9us : rcu_nmi_exit <-soft_nmi_interrupt
   <...>-550    90d...    9us : printk_nmi_exit <-soft_nmi_interrupt
   <...>-550    90d...   10us : cpuacct_charge <-update_curr_rt

The soft_nmi_interrupt here is the call into the watchdog, due to the
decrementer interrupt firing with irqs soft-disabled. This is
harmless, but sub-optimal.

When it's not called from NMI context or with interrupts enabled, mark
the decrementer pending in the irq_happened mask directly, rather than
having the masked decrementer interupt handler do it. This will be
replayed at the next local_irq_enable. See the comment for details.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:25 +10:00
Christophe Leroy
2479bfc9bc powerpc: Fix build by disabling attribute-alias warning for SYSCALL_DEFINEx
GCC 8.1 emits warnings such as the following. As arch/powerpc code is
built with -Werror, this breaks the build with GCC 8.1.

  In file included from arch/powerpc/kernel/pci_64.c:23:
  ./include/linux/syscalls.h:233:18: error: 'sys_pciconfig_iobase' alias
  between functions of incompatible types 'long int(long int, long
  unsigned int, long unsigned int)' and 'long int(long int, long int,
  long int)' [-Werror=attribute-alias]
    asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
                    ^~~
  ./include/linux/syscalls.h:222:2: note: in expansion of macro '__SYSCALL_DEFINEx'
    __SYSCALL_DEFINEx(x, sname, __VA_ARGS__)

This patch inhibits those warnings.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Trim change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:24 +10:00
Christophe Leroy
c959988118 powerpc/64: Fix strncpy() related build failures with GCC 8.1
GCC 8.1 warns about possible string truncation:

  arch/powerpc/kernel/nvram_64.c:1042:2: error: 'strncpy' specified
  bound 12 equals destination size [-Werror=stringop-truncation]
    strncpy(new_part->header.name, name, 12);

  arch/powerpc/platforms/ps3/repository.c:106:2: error: 'strncpy'
  output truncated before terminating nul copying 8 bytes from a
  string of the same length [-Werror=stringop-truncation]
    strncpy((char *)&n, text, 8);

Fix it by using memcpy(). To make that safe we need to ensure the
destination is pre-zeroed. Use kzalloc() in the nvram code and
initialise the u64 to zero in the ps3 code.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Use kzalloc() in the nvram code, flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:24 +10:00
Michael Ellerman
f1079d3a3d Merge branch 'fixes' into next
We ended up with an ugly conflict between fixes and next in ftrace.h
involving multiple nested ifdefs, and the automatic resolution is
wrong. So merge fixes into next so we can fix it up.
2018-06-03 20:32:02 +10:00
Michael Ellerman
b5240b1439 Merge branch 'topic/kbuild' into next
Merge in some commits we're sharing with the kbuild tree.
2018-06-03 20:24:15 +10:00
Michael Ellerman
481c63acba Merge branch 'topic/ppc-kvm' into next
Merge in some commits we're sharing with the kvm-ppc tree.
2018-06-03 20:23:54 +10:00
Mathieu Malaterre
8af1da4066 powerpc/prom: Fix %u/%llx usage since prom_printf() change
In commit eae5f709a4 ("powerpc: Add __printf verification to
prom_printf") __printf attribute was added to prom_printf(), which
means GCC started warning about type/format mismatches. As part of
that commit we changed some "%lx" formats to "%llx" where the type is
actually unsigned long long.

Unfortunately prom_printf() doesn't know how to print "%llx", it just
prints a literal "lx", eg:

  reserved memory map:
    lx - lx
    lx - lx

prom_printf() also doesn't know how to print "%u" (only "%lu"), it
just prints a literal "u", eg:

  Max number of cores passed to firmware: u (NR_CPUS = 2048)

Instead of:

  Max number of cores passed to firmware: 2048 (NR_CPUS = 2048)

This commit adds support for the missing formatters.

Fixes: eae5f709a4 ("powerpc: Add __printf verification to prom_printf")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-02 01:48:11 +10:00
Nicholas Piggin
af3901cbbd powerpc/kbuild: Remove CROSS32 defines from top level powerpc Makefile
Switch VDSO32 build over to use CROSS32_COMPILE directly, and have
it pass in -m32 after the standard c_flags. This allows endianness
overrides to be removed and the endian and bitness flags moved into
standard flags variables.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-01 23:08:06 +10:00
Paul Mackerras
43b812d9ab Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the ppc-kvm topic branch of the powerpc repository
to get some changes on which future patches will depend, in particular
some new exports and TEXASR bit definitions.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-31 09:27:10 +10:00
Aneesh Kumar K.V
5e3f0d15ae powerpc/livepatch: Fix build error with kprobes disabled.
arch/powerpc/kernel/stacktrace.c: In function ‘save_stack_trace_tsk_reliable’:
arch/powerpc/kernel/stacktrace.c:176:28: error: ‘kretprobe_trampoline’ undeclared
   if (ip == (unsigned long)kretprobe_trampoline)
                            ^~~~~~~~~~~~~~~~~~~~

Fixes: df78d3f614 ("powerpc/livepatch: Implement reliable stack tracing for the consistency model")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-29 11:10:39 +10:00
Josh Poimboeuf
8ce621e1d9 powerpc/modules: remove unused mod_arch_specific.toc field
The toc field in the mod_arch_specific struct isn't actually used
anywhere, so remove it.

Also the ftrace-specific fields are now common between 32-bit and
64-bit, so simplify the struct definition a bit by moving them out of
the __powerpc64__ #ifdef.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-28 18:46:34 +10:00
Linus Torvalds
ec30dcf7f4 KVM fixes for v4.17-rc7
PPC:
  - Close a hole which could possibly lead to the host timebase getting
    out of sync.
 
  - Three fixes relating to PTEs and TLB entries for radix guests.
 
  - Fix a bug which could lead to an interrupt never getting delivered
    to the guest, if it is pending for a guest vCPU when the vCPU gets
    offlined.
 
 s390:
  - Fix false negatives in VSIE validity check (Cc stable)
 
 x86:
  - Fix time drift of VMX preemption timer when a guest uses LAPIC timer
    in periodic mode (Cc stable)
 
  - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow
    migration from hosts that don't need retpoline mitigation (Cc stable)
 
  - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and
    CPUID.OSXSAVE (Cc stable)
 
  - Report correct RIP after Hyper-V hypercall #UD (introduced in -rc6)
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:
 "PPC:

   - Close a hole which could possibly lead to the host timebase getting
     out of sync.

   - Three fixes relating to PTEs and TLB entries for radix guests.

   - Fix a bug which could lead to an interrupt never getting delivered
     to the guest, if it is pending for a guest vCPU when the vCPU gets
     offlined.

  s390:

   - Fix false negatives in VSIE validity check (Cc stable)

  x86:

   - Fix time drift of VMX preemption timer when a guest uses LAPIC
     timer in periodic mode (Cc stable)

   - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow
     migration from hosts that don't need retpoline mitigation (Cc
     stable)

   - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and
     CPUID.OSXSAVE (Cc stable)

   - Report correct RIP after Hyper-V hypercall #UD (introduced in
     -rc6)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: fix #UD address of failed Hyper-V hypercalls
  kvm: x86: IA32_ARCH_CAPABILITIES is always supported
  KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
  x86/kvm: fix LAPIC timer drift when guest uses periodic mode
  KVM: s390: vsie: fix < 8k check for the itdba
  KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path
  KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change
  KVM: PPC: Book3S HV: Make radix clear pte when unmapping
  KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page
  KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry
2018-05-26 10:46:57 -07:00
Linus Torvalds
b133ef6ea4 powerpc fixes for 4.17 #7
Just one fix, to make sure the PCR (Processor Compatibility Register) is reset
 on boot. Otherwise if we're running in compat mode in a guest (eg. pretending a
 Power9 is a Power8) and the host kernel oopses and kdumps then the kdump
 kernel's userspace will be running in Power8 mode, and will SIGILL if it uses
 Power9-only instructions.
 
 Thanks to:
   Michael Neuling.
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Merge tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fix from Michael Ellerman:
 "Just one fix, to make sure the PCR (Processor Compatibility Register)
  is reset on boot.

  Otherwise if we're running in compat mode in a guest (eg. pretending a
  Power9 is a Power8) and the host kernel oopses and kdumps then the
  kdump kernel's userspace will be running in Power8 mode, and will
  SIGILL if it uses Power9-only instructions.

  Thanks to Michael Neuling"

* tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Clear PCR on boot
2018-05-25 09:32:00 -07:00
Mathieu Malaterre
d647b210ac powerpc: Add a missing include header
The header file <asm/switch_to.h> was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/vecemu.c:260:5: error: no previous prototype for ‘emulate_altivec’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:46 +10:00
Mathieu Malaterre
c89ca59322 powerpc/32: Add a missing include header
The header file <linux/syscalls.h> was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:46 +10:00
Mathieu Malaterre
9e0d86cd2d powerpc/tau: Make some function static
These functions can all be static, make it so. Fix warnings treated as
errors with W=1:

  arch/powerpc/kernel/tau_6xx.c:53:6: error: no previous prototype for ‘set_thresholds’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:73:6: error: no previous prototype for ‘TAUupdate’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:208:13: error: no previous prototype for ‘TAU_init_smp’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:220:12: error: no previous prototype for ‘TAU_init’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:126:6: error: no previous prototype for ‘TAUException’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:44 +10:00
Mathieu Malaterre
86e11b6e9c powerpc: Make function btext_initialize static
This function can be static, make it so, this fix a warning treated as
error with W=1:

  arch/powerpc/kernel/btext.c:173:5: error: no previous prototype for ‘btext_initialize’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:44 +10:00
Mathieu Malaterre
bd13ac95f9 powerpc/tau: Synchronize function prototypes and body
Some function prototypes and body for Thermal Assist Units were not in
sync. Update the function definition to match the existing function
declaration found in `setup-common.c`, changing an `int` return type to a
`u32` return type. Move the prototypes to a header file. Fix the following
warnings, treated as error with W=1:

  arch/powerpc/kernel/tau_6xx.c:257:5: error: no previous prototype for ‘cpu_temp_both’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:262:5: error: no previous prototype for ‘cpu_temp’ [-Werror=missing-prototypes]
  arch/powerpc/kernel/tau_6xx.c:267:5: error: no previous prototype for ‘tau_interrupts’ [-Werror=missing-prototypes]

Compile tested with CONFIG_TAU_INT.

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:43 +10:00
Mathieu Malaterre
85aa4b9841 powerpc/mm/radix: Use do/while(0) trick for single statement block
In commit 7a22d6321c ("powerpc/mm/radix: Update command line parsing for
disable_radix") an `if` statement was added for a possible empty body
(prom_debug).

Fix the following warning, treated as error with W=1:

  arch/powerpc/kernel/prom_init.c:656:46: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]

Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:39 +10:00
Mathieu Malaterre
d8731527ac powerpc/sparse: Fix plain integer as NULL pointer warning
Trivial fix to remove the following sparse warnings:

  arch/powerpc/kernel/module_32.c:112:74: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/module_32.c:117:74: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1155:28: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1230:20: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1385:36: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1752:23: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2084:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2110:32: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2167:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2183:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:277:20: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:155:67: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:247:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:249:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:252:37: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:127:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:148:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:44:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:57:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:87:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:160:31: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:167:22: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:274:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:285:31: warning: Using plain integer as NULL pointer
  arch/powerpc/include/asm/hugetlb.h:204:16: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/ppc_mmu_32.c:170:21: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:1227:23: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:65:24: warning: Using plain integer as NULL pointer

Also use `--fix` command line option from `script/checkpatch --strict` to
remove the following:

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #72: FILE: arch/powerpc/kernel/btext.c:160:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "!vbase"
  #80: FILE: arch/powerpc/kernel/btext.c:167:
  +	if (vbase == NULL)

  CHECK: Comparison to NULL could be written "!base"
  #89: FILE: arch/powerpc/kernel/btext.c:274:
  +	if (base == NULL)

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #98: FILE: arch/powerpc/kernel/btext.c:285:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "strstr"
  #117: FILE: arch/powerpc/kernel/module_32.c:117:
  +		if (strstr(secstrings + sechdrs[i].sh_name, ".debug") != NULL)

  CHECK: Comparison to NULL could be written "!Hash"
  #130: FILE: arch/powerpc/mm/ppc_mmu_32.c:170:
  +	if (Hash == NULL)

  CHECK: Comparison to NULL could be written "Hash"
  #143: FILE: arch/powerpc/mm/tlb_hash32.c:44:
  +	if (Hash != NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #152: FILE: arch/powerpc/mm/tlb_hash32.c:57:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #161: FILE: arch/powerpc/mm/tlb_hash32.c:87:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #170: FILE: arch/powerpc/mm/tlb_hash32.c:127:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #179: FILE: arch/powerpc/mm/tlb_hash32.c:148:
  +	if (Hash == NULL) {

  ERROR: space required after that ';' (ctx:VxV)
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "node"
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "!region"
  #201: FILE: arch/powerpc/platforms/powermac/pci.c:1227:
  +	if (region == NULL)

  CHECK: Comparison to NULL could be written "of_get_property"
  #214: FILE: arch/powerpc/platforms/powermac/setup.c:155:
  +		if (of_get_property(np, "cache-unified", NULL) != NULL && dc) {

  CHECK: Comparison to NULL could be written "!np"
  #223: FILE: arch/powerpc/platforms/powermac/setup.c:247:
  +		if (np == NULL)

  CHECK: Comparison to NULL could be written "np"
  #226: FILE: arch/powerpc/platforms/powermac/setup.c:249:
  +		if (np != NULL) {

  CHECK: Comparison to NULL could be written "l2cr"
  #230: FILE: arch/powerpc/platforms/powermac/setup.c:252:
  +			if (l2cr != NULL) {

  CHECK: Comparison to NULL could be written "via"
  #243: FILE: drivers/macintosh/via-pmu.c:277:
  +	if (via != NULL)

  CHECK: Comparison to NULL could be written "current_req"
  #252: FILE: drivers/macintosh/via-pmu.c:1155:
  +	if (current_req != NULL) {

  CHECK: Comparison to NULL could be written "!req"
  #261: FILE: drivers/macintosh/via-pmu.c:1230:
  +	if (req == NULL || pmu_state != idle

  CHECK: Comparison to NULL could be written "!req"
  #270: FILE: drivers/macintosh/via-pmu.c:1385:
  +			if (req == NULL) {

  CHECK: Comparison to NULL could be written "!pp"
  #288: FILE: drivers/macintosh/via-pmu.c:2084:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #297: FILE: drivers/macintosh/via-pmu.c:2110:
  +	if (count < 1 || pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #306: FILE: drivers/macintosh/via-pmu.c:2167:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "pp"
  #315: FILE: drivers/macintosh/via-pmu.c:2183:
  +	if (pp != NULL) {

Link: https://github.com/linuxppc/linux/issues/37
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:38 +10:00
Mathieu Malaterre
eae5f709a4 powerpc: Add __printf verification to prom_printf
__printf is useful to verify format and arguments. Fix arg mismatch
reported by gcc, remove the following warnings (with W=1):

  arch/powerpc/kernel/prom_init.c:1467:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1471:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1504:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1505:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1506:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1507:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1508:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1509:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:1975:39: error: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘unsigned int’
  arch/powerpc/kernel/prom_init.c:1986:27: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2567:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2567:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2569:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
  arch/powerpc/kernel/prom_init.c:2569:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’

The patch also include arg mismatch fix for case with #define DEBUG_PROM
(warning not listed here).

This patch fix also the following warnings revealed by checkpatch:

  WARNING: Prefer using '"%s...", __func__' to using 'alloc_up', this function's name, in a string
  #101: FILE: arch/powerpc/kernel/prom_init.c:1235:
  + prom_debug("alloc_up(%lx, %lx)\n", size, align);

and

  WARNING: Prefer using '"%s...", __func__' to using 'alloc_down', this function's name, in a string
  #138: FILE: arch/powerpc/kernel/prom_init.c:1278:
  + prom_debug("alloc_down(%lx, %lx, %s)\n", size, align,

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:37 +10:00
Christophe Leroy
e4ccb1dae6 powerpc/8xx: fix invalid register expression in head_8xx.S
New binutils generate the following warning

  AS      arch/powerpc/kernel/head_8xx.o
arch/powerpc/kernel/head_8xx.S: Assembler messages:
arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression

This patch fixes it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:26 +10:00
Simon Guo
eacbb218fb powerpc: Export tm_enable()/tm_disable/tm_abort() APIs
This patch exports tm_enable()/tm_disable/tm_abort() APIs, which
will be used for PR KVM transactional memory logic.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-24 16:04:02 +10:00
Simon Guo
d1c7211281 powerpc: Export msr_check_and_set() to modules
PR KVM will need to reuse msr_check_and_set().
This patch exports this API for reuse.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-24 16:03:24 +10:00
Nicholas Piggin
a048a07d7f powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit
On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.

This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.

Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.

Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.

Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.

Thanks to Michal Suchánek for bug fixes and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-21 20:45:31 -07:00
Michael Neuling
4f7c06e26e powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG
In commit e2a800beac ("powerpc/hw_brk: Fix off by one error when
validating DAWR region end") we fixed setting the DAWR end point to
its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke
PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint.

PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to
zero (memset() in hw_breakpoint_init()). This worked with
arch_validate_hwbkpt_settings() before the above patch was applied but
is now broken if the breakpoint is 512byte aligned.

This sets the length of the breakpoint to 8 bytes when using
PTRACE_SET_DEBUGREG.

Fixes: e2a800beac ("powerpc/hw_brk: Fix off by one error when validating DAWR region end")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-21 14:48:01 +10:00
Michael Neuling
cd6ef7eebf powerpc/ptrace: Fix enforcement of DAWR constraints
Back when we first introduced the DAWR, in commit 4ae7ebe952
("powerpc: Change hardware breakpoint to allow longer ranges"), we
screwed up the constraint making it a 1024 byte boundary rather than a
512. This makes the check overly permissive. Fortunately GDB is the
only real user and it always did they right thing, so we never
noticed.

This fixes the constraint to 512 bytes.

Fixes: 4ae7ebe952 ("powerpc: Change hardware breakpoint to allow longer ranges")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-21 14:47:44 +10:00
Colin Ian King
ba01b058a5 powerpc/rtas: Fix spelling mistake "Discharching" -> "Discharging"
Trivial fix to spelling mistake in battery_charging array.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-18 21:55:01 +10:00
Michael Neuling
faf37c44a1 powerpc/64s: Clear PCR on boot
Clear the PCR (Processor Compatibility Register) on boot to ensure we
are not running in a compatibility mode.

We've seen this cause problems when a crash (and kdump) occurs while
running compat mode guests. The kdump kernel then runs with the PCR
set and causes problems. The symptom in the kdump kernel (also seen in
petitboot after fast-reboot) is early userspace programs taking
sigills on newer instructions (seen in libc).

Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-18 16:05:15 +10:00
Simon Guo
173c520a04 KVM: PPC: Move nip/ctr/lr/xer registers to pt_regs in kvm_vcpu_arch
This patch moves nip/ctr/lr/xer registers from scattered places in
kvm_vcpu_arch to pt_regs structure.

cr register is "unsigned long" in pt_regs and u32 in vcpu->arch.
It will need more consideration and may move in later patches.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-18 15:38:23 +10:00
Simon Guo
1143a70665 KVM: PPC: Add pt_regs into kvm_vcpu_arch and move vcpu->arch.gpr[] into it
Current regs are scattered at kvm_vcpu_arch structure and it will
be more neat to organize them into pt_regs structure.

Also it will enable reimplementation of MMIO emulation code with
analyse_instr() later.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-18 15:38:23 +10:00
Paul Mackerras
9c9e9cf40a Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the ppc-kvm topic branch of the powerpc repository
to get some changes on which future patches will depend, in particular
the definitions of various new TLB flushing functions.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-18 15:30:10 +10:00
Christophe Leroy
a1f3ae3fe8 powerpc/32: Use stmw/lmw for registers save/restore in asm
arch/powerpc/Makefile activates -mmultiple on BE PPC32 configs
in order to use multiple word instructions in functions entry/exit.

The patch does the same for the asm parts, for consistency.

On processors like the 8xx on which insn fetching is pretty slow,
this speeds up registers save/restore.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: PPC32 is BE only, so drop the endian checks]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-18 00:09:06 +10:00
Christophe Leroy
24c78586cc powerpc: Avoid an unnecessary test and branch in longjmp()
Doing the test at exit of the function avoids an unnecessary
test and branch inside longjmp().

Semantics are unchanged.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-18 00:09:05 +10:00
Nicholas Piggin
4c1d9bb0b5 powerpc: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selected
This requires further changes to linker script to KEEP some tables
and wildcard compiler generated sections into the right place. This
includes pp32 modifications from Christophe Leroy.

When compiling powernv_defconfig with this option, the resulting
kernel is almost 400kB smaller (and still boots):

    text      data       bss        dec   filename
11827621   4810490   1341080   17979191   vmlinux
11752437   4598858   1338776   17690071   vmlinux.dcde

Mathieu's numbers for custom Mac Mini G4 config has almost 200kB
saving. It also had some increase in vmlinux size for as-yet
unknown reasons.

    text      data       bss        dec   filename
 7461457   2475122   1428064   11364643   vmlinux
 7386425   2364370   1425432   11176227   vmlinux.dcde

Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> [8xx]
Tested-by: Mathieu Malaterre <malat@debian.org> [32-bit powermac]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-17 22:45:01 +09:00
Paul Mackerras
57b8daa70a KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry
Currently, the HV KVM guest entry/exit code adds the timebase offset
from the vcore struct to the timebase on guest entry, and subtracts
it on guest exit.  Which is fine, except that it is possible for
userspace to change the offset using the SET_ONE_REG interface while
the vcore is running, as there is only one timebase offset per vcore
but potentially multiple VCPUs in the vcore.  If that were to happen,
KVM would subtract a different offset on guest exit from that which
it had added on guest entry, leading to the timebase being out of sync
between cores in the host, which then leads to bad things happening
such as hangs and spurious watchdog timeouts.

To fix this, we add a new field 'tb_offset_applied' to the vcore struct
which stores the offset that is currently applied to the timebase.
This value is set from the vcore tb_offset field on guest entry, and
is what is subtracted from the timebase on guest exit.  Since it is
zero when the timebase offset is not applied, we can simplify the
logic in kvmhv_start_timing and kvmhv_accumulate_time.

In addition, we had secondary threads reading the timebase while
running concurrently with code on the primary thread which would
eventually add or subtract the timebase offset from the timebase.
This occurred while saving or restoring the DEC register value on
the secondary threads.  Although no specific incorrect behaviour has
been observed, this is a race which should be fixed.  To fix it, we
move the DEC saving code to just before we call kvmhv_commence_exit,
and the DEC restoring code to after the point where we have waited
for the primary thread to switch the MMU context and add the timebase
offset.  That way we are sure that the timebase contains the guest
timebase value in both cases.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-17 15:16:45 +10:00
Mathieu Malaterre
9f9eae5ce7 powerpc/kvm: Prefer fault_in_pages_readable function
Directly use fault_in_pages_readable instead of manual __get_user code. Fix
warning treated as error with W=1:

  arch/powerpc/kernel/kvm.c:675:6: error: variable ‘tmp’ set but not used [-Werror=unused-but-set-variable]

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-17 14:12:40 +10:00
Christoph Hellwig
3f3942aca6 proc: introduce proc_create_single{,_data}
Variants of proc_create{,_data} that directly take a seq_file show
callback and drastically reduces the boilerplate code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:23:35 +02:00
Michael Ellerman
89c1906272 powerpc/prom: Drop support for old FDT versions
In commit e6a6928c3e ("of/fdt: Convert FDT functions to use
libfdt") (Apr 2014), the generic flat device tree code dropped support
for flat device tree's older than version 0x10 (16).

We still have code in our CPU scanning to cope with flat device tree
versions earlier than 2, which can now never trigger, so drop it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-11 23:29:04 +10:00
Michael Ellerman
53da14d083 powerpc: Make it clearer that systbl check errors are errors
If the systbl_chk.sh checks fail we print a message, but with no
indication that it's an error. That makes it hard to find in build
logs with eg. grep.

So prefix any output with "Error:".

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:16 +10:00
Al Viro
28b9c34aa6 powerpc/syscalls: kill ppc32_select()
it had always been pointless - compat_sys_select() sign-extends
the first argument just fine on its own.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mpe: Use COMPAT_SPU_NEW() to keep systbl_chk.sh happy]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:15 +10:00
Michael Ellerman
454d7ef81a powerpc/syscalls: Add COMPAT_SPU_NEW() macro
Currently the select system call is wired up with the SYSX_SPU()
macro. The SYSX_SPU() is not handled by systbl_chk.c, which means the
syscall number for select is not checked.

That hides the fact that the syscall number for select is actually
__NR__newselect not __NR_select.

In a following patch we'd like to drop ppc32_select() which means
select will become a regular COMPAT_SYS_SPU() syscall. But
COMPAT_SYS_SPU() can't deal with the fact that the syscall number is
actually __NR__newselect. We also can't just redefine __NR_select
because that's still used for the old select call.

So add a new COMPAT_NEW_SPU() that does the same thing as
COMPAT_SYS_SPU() except it encodes that we're using the new number.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:14 +10:00
Al Viro
4c392e6591 powerpc/syscalls: switch rtas(2) to SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mpe: Update sys_ni.c for s/ppc_rtas/sys_rtas/]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:14 +10:00
Al Viro
f3675644e1 powerpc/syscalls: signal_{32, 64} - switch to SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mpe: Fix sys_debug_setcontext() prototype to return long]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:13 +10:00
Al Viro
3691d61455 powerpc/syscalls: Switch trivial cases to SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:12 +10:00
Torsten Duwe
df78d3f614 powerpc/livepatch: Implement reliable stack tracing for the consistency model
The "Power Architecture 64-Bit ELF V2 ABI" says in section 2.3.2.3:

[...] There are several rules that must be adhered to in order to ensure
reliable and consistent call chain backtracing:

* Before a function calls any other function, it shall establish its
  own stack frame, whose size shall be a multiple of 16 bytes.

 – In instances where a function’s prologue creates a stack frame, the
   back-chain word of the stack frame shall be updated atomically with
   the value of the stack pointer (r1) when a back chain is implemented.
   (This must be supported as default by all ELF V2 ABI-compliant
   environments.)
[...]
 – The function shall save the link register that contains its return
   address in the LR save doubleword of its caller’s stack frame before
   calling another function.

To me this sounds like the equivalent of HAVE_RELIABLE_STACKTRACE.
This patch may be unneccessarily limited to ppc64le, but OTOH the only
user of this flag so far is livepatching, which is only implemented on
PPCs with 64-LE, a.k.a. ELF ABI v2.

Feel free to add other ppc variants, but so far only ppc64le got tested.

This change also implements save_stack_trace_tsk_reliable() for ppc64le
that checks for the above conditions, where possible.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Nicolai Stange <nstange@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:12 +10:00
Nicholas Piggin
4e49226ea8 powerpc/watchdog: provide more data in watchdog messages
Provide timebase and timebase of last heartbeat in watchdog lockup
messages. Also provide a stack trace of when a CPU becomes un-stuck,
which can be useful -- it could be where irqs are re-enabled, so it
may be the end of the critical section which is responsible for the
latency which is useful information.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:11 +10:00
Nicholas Piggin
5a951c4e7e powerpc/watchdog: don't update the watchdog timestamp if a lockup is detected
The watchdog heartbeat timestamp is updated when the local heartbeat
timer fires (or touch_nmi_watchdog() is called).

This is an interesting data point, so don't overwrite it when the
soft-NMI interrupt detects a hard lockup. That code came from a pre-
merge version to prevent hard lockup messages flood, but that's taken
care of with the stuck CPU logic now, so there is no reason to
update the heartbeat timestamp here.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:11 +10:00
Cédric Le Goater
d2b04b0c78 powerpc/64/kexec: fix race in kexec when XIVE is shutdown
The kexec_state KEXEC_STATE_IRQS_OFF barrier is reached by all
secondary CPUs before the kexec_cpu_down() operation is called on
secondaries. This can raise conflicts and provoque errors in the XIVE
hcalls when XIVE is shutdown with H_INT_RESET on the primary CPU.

To synchronize the kexec_cpu_down() operations and make sure the
secondaries have completed their task before the primary starts doing
the same, let's move the primary kexec_cpu_down() after the
KEXEC_STATE_REAL_MODE barrier.

This change of the ending sequence of kexec is mostly useful on the
pseries platform but it impacts also the powernv, ps3 and 85xx
platforms. powernv can be easily tested and fixed but some caution is
required for the other two.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:08 +10:00