Remove an unnecessary piece of code that does an endianness conversion
but does not use the result. The following warning was reported by
Clang's static analyzer:
arch/powerpc/sysdev/xics/ics-opal.c:114:2: warning: Value stored to
'server' is never read [deadcode.DeadStores]
server = be16_to_cpu(oserver);
'server' was used as a parameter to opal_get_xive() in commit
5c7c1e9444 ("powerpc/powernv: Add OPAL ICS backend") when it was
introduced. 'server' was also used in an error message for the call to
opal_get_xive().
'server' was always later set by a call to ics_opal_mangle_server()
before being used.
Commit bf8e0f891a ("powerpc/powernv: Fix endian issues in OPAL ICS
backend") used a new variable 'oserver' as the parameter to
opal_get_xive() instead of 'server' for endian correctness. It also
removed 'server' from the error message for the call to opal_get_xive().
Fix the warning by removing the server variable assignment.
Fixes: bf8e0f891a ("powerpc/powernv: Fix endian issues in OPAL ICS backend")
Reviewed-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230731115543.36991-1-gautam@linux.ibm.com
If device_register() returns error in ibmebus_bus_init(), name of kobject
which is allocated in dev_set_name() called in device_add() is leaked.
As comment of device_add() says, it should call put_device() to drop
the reference count that was set in device_initialize() when it fails,
so the name can be freed in kobject_cleanup().
Signed-off-by: ruanjinjie <ruanjinjie@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20221110011929.3709774-1-ruanjinjie@huawei.com
Commit ddb5cdbafa ("kbuild: generate KSYMTAB entries by modpost")
deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>.
Replace #include <asm/export.h> with #include <linux/export.h>.
After all the <asm/export.h> lines are converted, <asm/export.h> and
<asm-generic/export.h> will be removed.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
[mpe: Fixup selftests that stub asm/export.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230806150954.394189-2-masahiroy@kernel.org
PCI core add pci_find_vsec_capability() to query VSEC. We can use that
core API to simplify the code.
The only logical change is that pci_find_vsec_capability check the
Vendor ID before finding the VSEC.
PCI spec rev 5.0 says in 7.9.5.2 Vendor-Specific Header:
VSEC ID - This field is a vendor-defined ID number that indicates the
nature and format of the VSEC structure
Software must qualify the Vendor ID before interpreting this field.
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230804075630.186054-1-wangxiongfeng2@huawei.com
With skiboot_defconfig, Clang reports:
CC arch/powerpc/mm/book3s64/radix_tlb.o
arch/powerpc/mm/book3s64/radix_tlb.c:419:20: error: unused function '_tlbie_pid_lpid' [-Werror,-Wunused-function]
static inline void _tlbie_pid_lpid(unsigned long pid, unsigned long lpid,
^
arch/powerpc/mm/book3s64/radix_tlb.c:663:20: error: unused function '_tlbie_va_range_lpid' [-Werror,-Wunused-function]
static inline void _tlbie_va_range_lpid(unsigned long start, unsigned long end,
^
This is because those functions are only called from functions
enclosed in a #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
Move below functions inside that #ifdef
* __tlbie_pid_lpid(unsigned long pid,
* __tlbie_va_lpid(unsigned long va, unsigned long pid,
* fixup_tlbie_pid_lpid(unsigned long pid, unsigned long lpid)
* _tlbie_pid_lpid(unsigned long pid, unsigned long lpid,
* fixup_tlbie_va_range_lpid(unsigned long va,
* __tlbie_va_range_lpid(unsigned long start, unsigned long end,
* _tlbie_va_range_lpid(unsigned long start, unsigned long end,
Fixes: f0c6fbbb90 ("KVM: PPC: Book3S HV: Add support for H_RPT_INVALIDATE")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307260802.Mjr99P5O-lkp@intel.com/
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/3d72efd39f986ee939d068af69fdce28bd600766.1691568093.git.christophe.leroy@csgroup.eu
Randconfig testing with W=1 showed up these warnings that I'd like to enable
by default:
arch/powerpc/xmon/xmon.c: In function 'dump_tlb_book3e':
arch/powerpc/xmon/xmon.c:3833:42: error: variable 'lrat' set but not used [-Werror=unused-but-set-variable]
3833 | int i, tlb, ntlbs, pidsz, lpidsz, rasz, lrat = 0;
| ^~~~
arch/powerpc/xmon/xmon.c:3831:23: error: variable 'lpidmask' set but not used [-Werror=unused-but-set-variable]
3831 | u32 mmucfg, pidmask, lpidmask;
| ^~~~~~~~
arch/powerpc/xmon/xmon.c:3831:14: error: variable 'pidmask' set but not used [-Werror=unused-but-set-variable]
3831 | u32 mmucfg, pidmask, lpidmask;
| ^~~~~~~
Just remove these as they have been unused since the code was added in 2010.
Fixes: 03247157f7 ("powerpc/book3e: Add TLB dump in xmon for Book3E")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230809131024.2039647-2-arnd@kernel.org
A while ago I created a2305e3de8 ("powerpc: mark local variables
around longjmp as volatile") in order to allow building powerpc with
-Wextra enabled on gcc-11.
I tried this again with gcc-13 and found two more of the same issues,
presumably based on slightly different optimization paths being taken
here:
arch/powerpc/xmon/xmon.c:3306:27: error: variable 'mm' might be clobbered by 'longjmp' or 'vfork' [-Werror=clobbered]
arch/powerpc/kexec/crash.c:353:22: error: variable 'i' might be clobbered by 'longjmp' or 'vfork' [-Werror=clobbered]
I checked a bunch of randconfigs and found only these two, so just
address them the same way as the others.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230809131024.2039647-1-arnd@kernel.org
Add support for HOTPLUG_SMT, which enables the generic sysfs SMT support
files in /sys/devices/system/cpu/smt, as well as the "nosmt" boot
parameter.
Implement the recently added hooks to allow partial SMT states, allow
any number of threads per core.
Tie the config symbol to HOTPLUG_CPU, which enables it on the major
platforms that support SMT. If there are other platforms that want the
SMT support that can be tweaked in future.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
[ldufour: remove topology_smt_supported]
[ldufour: remove topology_smt_threads_supported]
[ldufour: select CONFIG_SMT_NUM_THREADS_DYNAMIC]
[ldufour: update kernel-parameters.txt]
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Link: https://msgid.link/20230705145143.40545-10-ldufour@linux.ibm.com
As part of the generic HOTPLUG_SMT code, there is support for disabling
secondary SMT threads at boot time, by passing "nosmt" on the kernel
command line.
The way that is implemented is the secondary threads are brought partly
online, and then taken back offline again. That is done to support x86
CPUs needing certain initialisation done on all threads. However powerpc
has similar needs, see commit d70a54e2d0 ("powerpc/powernv: Ignore
smt-enabled on Power8 and later").
For that to work the powerpc CPU hotplug callbacks need to be registered
before secondary CPUs are brought online, otherwise __cpu_disable()
fails due to smp_ops->cpu_disable being NULL.
So split the basic initialisation into pseries_cpu_hotplug_init() which
can be called early from setup_arch(). The DLPAR related initialisation
can still be done later, because it needs to do allocations.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230705145143.40545-9-ldufour@linux.ibm.com
There are a few warnings in powerpc64 defconfig builds after -Wmissing-prototypes
gets promoted from W=1 to the default warning set:
arch/powerpc/mm/book3s64/pgtable.c:422:6: error: no previous prototype for 'arch_report_meminfo' [-Werror=missing-prototypes]
arch/powerpc/platforms/cell/ras.c:275:5: error: no previous prototype for 'cbe_sysreset_hack' [-Werror=missing-prototypes]
arch/powerpc/platforms/cell/spu_manage.c:29:21: error: no previous prototype for 'spu_devnode' [-Werror=missing-prototypes]
arch/powerpc/platforms/pasemi/time.c:12:17: error: no previous prototype for 'pas_get_boot_time' [-Werror=missing-prototypes]
arch/powerpc/platforms/powermac/feature.c:1532:13: error: no previous prototype for 'g5_phy_disable_cpu1' [-Werror=missing-prototypes]
arch/powerpc/platforms/86xx/pic.c:28:13: error: no previous prototype for 'mpc86xx_init_irq' [-Werror=missing-prototypes]
drivers/pci/pci-sysfs.c:936:13: error: no previous prototype for 'pci_adjust_legacy_attr' [-Werror=missing-prototypes]
Address these by including the right header files or marking the
functions static. The audit.c one is a bit tricky since compat_audit.h
cannot include regular kernel headers tht have conflicting types on
32-bit powerpc.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[mpe: Drop change to __vmemmap_free() which only exists in mm]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230727122720.2558065-1-arnd@kernel.org
While the target is volatile, the temporary variables used to access the
target cast away the volatile. This is undefined behaviour, and a
compiler may optimise away/reorder these accesses, breaking the test.
This was observed with GCC 13.1.1, but it can be difficult to reproduce
because of the dependency on compiler behaviour.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230725005841.28854-5-bgray@linux.ibm.com
Many tests require specific hardware features/configurations that a
typical machine might not have. As a result, it's common to see a test
is skipped. But it is tedious to find out why a test is skipped
when all it gives is the file location of the skip macro.
Convert SKIP_IF() to SKIP_IF_MSG(), with appropriate descriptions of why
the test is being skipped. This gives a general idea of why a test is
skipped, which can be looked into further if it doesn't make sense.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230725005841.28854-3-bgray@linux.ibm.com
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.
Signed-off-by: Rob Herring <robh@kernel.org>
[mpe: Fixup maple/setup.c which needs platform_device]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230724210247.778034-1-robh@kernel.org
This performs lazy tlb mm shootdown when doing the exit TLB flush when
all mm users go away and user mappings are removed, which avoids having
to do the lazy tlb mm shootdown IPIs on the final mmput when all kernel
references disappear.
powerpc/64s uses a broadcast TLBIE for the exit TLB flush if remote CPUs
need to be invalidated (unless TLBIE is disabled), so this doesn't
necessarily save IPIs but it does avoid a broadcast TLBIE which is quite
expensive.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Squash in preempt_disable/enable() fix from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-5-npiggin@gmail.com
When context switching away from an mm, add a CONFIG_DEBUG_VM warning
check to ensure this CPU is still set in the mask. This could catch
bugs where the mask is improperly trimmed while the CPU is still using
the mm.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-4-npiggin@gmail.com
init_mm mm_cpumask and context.active_cpus is not maintained at boot
and hotplug. This seems to be harmless because init_mm does not have a
userspace and so never gets user TLBs flushed, but it looks odd and it
prevents some sanity checks being added.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-2-npiggin@gmail.com
Objtool reports following warnings:
arch/powerpc/kernel/signal_32.o: warning: objtool:
__prevent_user_access.constprop.0+0x4 (.text+0x4):
redundant UACCESS disable
arch/powerpc/kernel/signal_32.o: warning: objtool: user_access_begin+0x2c
(.text+0x4c): return with UACCESS enabled
arch/powerpc/kernel/signal_32.o: warning: objtool: handle_rt_signal32+0x188
(.text+0x360): call to __prevent_user_access.constprop.0() with UACCESS enabled
arch/powerpc/kernel/signal_32.o: warning: objtool: handle_signal32+0x150
(.text+0x4d4): call to __prevent_user_access.constprop.0() with UACCESS enabled
This is due to some KUAP enabling/disabling functions being outline
allthough they are marked inline. Use __always_inline instead.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/ca5e50ddbec3867db5146ebddbc9a1dc0e443bc8.1689091022.git.christophe.leroy@csgroup.eu
On book3s/32 KUAP is performed at segment level. At the moment,
when enabling userspace access, only current segment is modified.
Then if a write is performed on another user segment, a fault is
taken and all other user segments get enabled for userspace
access. This then require special attention when disabling
userspace access.
Having a userspace write access crossing a segment boundary is
unlikely. Having a userspace write access crossing a segment boundary
back and forth is even more unlikely. So, instead of enabling
userspace access on all segments when a write fault occurs, just
change which segment has userspace access enabled in order to
eliminate the case when more than one segment has userspace access
enabled. That simplifies userspace access deactivation.
There is however a corner case which is even more unlikely but has
to be handled anyway: an unaligned access which is crossing a
segment boundary. That would definitely require at least having
userspace access enabled on the two segments. To avoid complicating
the likely case for a so unlikely happening, handle such situation
like an alignment exception and emulate the store.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/8de8580513c1a6e880bad1ba9a69d3efad3d4fa5.1689091022.git.christophe.leroy@csgroup.eu
A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MD_AP register. This is shown by r9 being re-used immediately without
doing anything with the value read.
c000e0e0: 60 00 00 00 nop
c000e0e4: ===> 7d 3a c2 a6 mfmd_ap r9 <====
c000e0e8: 7d 20 00 a6 mfmsr r9
c000e0ec: 7c 51 13 a6 mtspr 81,r2
c000e0f0: 81 3f 00 84 lwz r9,132(r31)
c000e0f4: 71 29 80 00 andi. r9,r9,32768
kuap_get_and_assert_locked() is paired with kuap_kernel_restore()
and are only used in interrupt_exit_kernel_prepare(). The value
returned by kuap_get_and_assert_locked() is only used by
kuap_kernel_restore().
On 8xx, kuap_kernel_restore() doesn't use the value read by
kuap_get_and_assert_locked() so modify kuap_get_and_assert_locked()
to not perform the read of MD_AP and return 0 instead.
The same applies on BOOKE.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/bcbc84c2dd90bb1021da792b1968cdc22112dad8.1689091022.git.christophe.leroy@csgroup.eu
