On PPC64, we have mftb().
On PPC32, we have mftbl() and an #define mftb() mftbl().
mftb() and mftbl() are equivalent, their purpose is to read the
content of SPRN_TRBL, as returned by 'mftb' simplified instruction.
binutils seems to define 'mftbl' instruction as an equivalent
of 'mftb'.
However in both 32 bits and 64 bits documentation, only 'mftb' is
defined, and when performing a disassembly with objdump, the displayed
instruction is 'mftb'
No need to have two ways to do the same thing with different
names, rename mftbl() to have only mftb().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/94dc68d3d9ef9eb549796d4b938b6ba0305a049b.1601556145.git.christophe.leroy@csgroup.eu
Unlike PPC64 which had a single head_64.S, PPC32 are multiple ones.
There is the head_32.S, selected by default based on the value of BITS
and overridden based on some CONFIG_ values. This leads to thinking
that it may be selected by different types of PPC32 platform but
indeed it ends up being selected by book3s/32 only.
Make that explicit by:
- Not doing any default selection based on BITS.
- Renaming head_32.S to head_book3s_32.S.
- Get head_book3s_32.S selected only by CONFIG_PPC_BOOK3S_32.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix head_$(BITS).o reference in arch/powerpc/Makefile]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/319d379f696412681c66a987cc75e6abf8f958d2.1601975100.git.christophe.leroy@csgroup.eu
At the time being, an early hash table is set up when
CONFIG_KASAN is selected.
There is nothing wrong with setting such an early hash table
all the time, even if it is not used. This is a statically
allocated 256 kB table which lies in the init data section.
This makes the code simpler and may in the future allow to
setup early IO mappings with fixmap instead of hard coding BATs.
Put create_hpte() and flush_hash_pages() in the .ref.text section
in order to avoid warning for the reference to early_hash[]. This
reference is removed by MMU_init_hw_patch() before init memory is
freed.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b8f8101c368b8a6451844a58d7bd7d83c14cf2aa.1601566529.git.christophe.leroy@csgroup.eu
Add asm/mce.h to asm/asm-prototypes.h so that that asm symbol's checksum
can be generated in order to support CONFIG_MODVERSIONS with it and fix:
WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version \
generation failed, symbol will not be versioned.
For reference see:
4efca4ed05 ("kbuild: modversions for EXPORT_SYMBOL() for asm")
334bb77387 ("x86/kbuild: enable modversions for symbols exported from asm")
Fixes: ec6347bb43 ("x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()")
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201007111447.GA23257@zn.tnic
SGI-IP28 systems only use broken R10k rev 2.5 CPUs, which could lock
up, if ll/sc sequences are issued in certain order. Since those systems
are all non-SMP, we can disable ll/sc usage in kernel.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Add NVDIMM_FAMILY_PAPR to the list of valid 'dimm_family_mask'
acceptable by papr_scm. This is needed as since commit
92fe2aa859 ("libnvdimm: Validate command family indices") libnvdimm
performs a validation of 'nd_cmd_pkg.nd_family' received as part of
ND_CMD_CALL processing to ensure only known command families can use
the general ND_CMD_CALL pass-through functionality.
Without this change the ND_CMD_CALL pass-through targeting
NVDIMM_FAMILY_PAPR error out with -EINVAL.
Fixes: 92fe2aa859 ("libnvdimm: Validate command family indices")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200913211904.24472-1-vaibhav@linux.ibm.com
The inline execution path for the hardware assisted branch flush
instruction failed to set CTR to the correct value before bcctr,
causing a crash when the feature is enabled.
Fixes: 4d24e21cc6 ("powerpc/security: Allow for processors that flush the link stack using the special bcctr")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201007080605.64423-1-npiggin@gmail.com
Add support for AP bus adapter config and deconfig to the sclp
core code. The code is statically build into the kernel when
ZCRYPT is configured either as module or with static support.
This is the base functionality for having configure/deconfigure
support in the AP bus and card code. Another patch will exploit
this soon.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Suggested-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Currently, the MOVDIR64B instruction is used to atomically submit
64-byte work descriptors to devices. Although it can encounter errors
like device queue full, command not accepted, device not ready, etc when
writing to a device MMIO, MOVDIR64B can not report back on errors from
the device itself. This means that MOVDIR64B users need to separately
interact with a device to see if a descriptor was successfully queued,
which slows down device interactions.
ENQCMD and ENQCMDS also atomically submit 64-byte work descriptors
to devices. But, they *can* report back errors directly from the
device, such as if the device was busy, or device not enabled or does
not support the command. This immediate feedback from the submission
instruction itself reduces the number of interactions with the device
and can greatly increase efficiency.
ENQCMD can be used at any privilege level, but can effectively only
submit work on behalf of the current process. ENQCMDS is a ring0-only
instruction and can explicitly specify a process context instead of
being tied to the current process or needing to reprogram the IA32_PASID
MSR.
Use ENQCMDS for work submission within the kernel because a Process
Address ID (PASID) is setup to translate the kernel virtual address
space. This PASID is provided to ENQCMDS from the descriptor structure
submitted to the device and not retrieved from IA32_PASID MSR, which is
setup for the current user address space.
See Intel Software Developer’s Manual for more information on the
instructions.
[ bp:
- Make operand constraints like movdir64b() because both insns are
basically doing the same thing, more or less.
- Fixup comments and cleanup. ]
Link: https://lkml.kernel.org/r/20200924180041.34056-3-dave.jiang@intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20201005151126.657029-3-dave.jiang@intel.com
Late patches for 5.10: MTE selftests, minor KCSAN preparation and removal
of some unused prototypes.
(Amit Daniel Kachhap and others)
* for-next/late-arrivals:
arm64: random: Remove no longer needed prototypes
arm64: initialize per-cpu offsets earlier
kselftest/arm64: Check mte tagged user address in kernel
kselftest/arm64: Verify KSM page merge for MTE pages
kselftest/arm64: Verify all different mmap MTE options
kselftest/arm64: Check forked child mte memory accessibility
kselftest/arm64: Verify mte tag inclusion via prctl
kselftest/arm64: Add utilities and a test to validate mte memory
Commit 9bceb80b3c ("arm64: kaslr: Use standard early random
function") removed the direct calls of the __arm64_rndr() and
__early_cpu_has_rndr() functions, but left the dummy prototypes in the
#else branch of the #ifdef CONFIG_ARCH_RANDOM guard.
Remove the redundant prototypes, as they have no users outside of
this header file.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20201006194453.36519-1-andre.przywara@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Patch here adds a cpumask attr to hv_gpci pmu along with ABI documentation.
Primary use to expose the cpumask is for the perf tool which has the
capability to parse the driver sysfs folder and understand the
cpumask file. Having cpumask file will reduce the number of perf command
line parameters (will avoid "-C" option in the perf tool
command line). It can also notify the user which is
the current cpu used to retrieve the counter data.
command:# cat /sys/devices/hv_gpci/cpumask
0
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201003074943.338618-5-kjain@linux.ibm.com
Patch here adds cpu hotplug functions to hv_gpci pmu.
A new cpuhp_state "CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE" enum
is added.
The online callback function updates the cpumask only if its
empty. As the primary intention of adding hotplug support
is to designate a CPU to make HCALL to collect the
counter data.
The offline function test and clear corresponding cpu in a cpumask
and update cpumask to any other active cpu.
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201003074943.338618-4-kjain@linux.ibm.com
Commit 9e9f601084 ("powerpc/perf/{hv-gpci, hv-common}: generate
requests with counters annotated") adds a framework for defining
gpci counters.
In this patch, they adds starting_index value as '0xffffffffffffffff'.
which is wrong as starting_index is of size 32 bits.
Because of this, incase we try to run hv-gpci event we get error.
In power9 machine:
command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
-C 0 -I 1000
event syntax error: '..bie_count_and_time_tlbie_instructions_issued/'
\___ value too big for format, maximum is 4294967295
This patch fix this issue and changes starting_index value to '0xffffffff'
After this patch:
command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ -C 0 -I 1000
1.000085786 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
2.000287818 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
2.439113909 17,408 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
Fixes: 9e9f601084 ("powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201003074943.338618-1-kjain@linux.ibm.com
If the RTAS call to query the PE address for a device fails we jump the
err: label where an error message is printed along with the return code.
However, the printed return code is from the "ret" variable which isn't set
at that point since we assigned the result to "addr" instead. Fix this by
consistently using the "ret" variable for the result of the RTAS call
helpers an dropping the "addr" local variable"
Fixes: 98ba956f6a ("powerpc/pseries/eeh: Rework device EEH PE determination")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201007040903.819081-2-oohall@gmail.com
All instructions copying data between kernel and user memory
are tagged with either _ASM_EXTABLE_UA or _ASM_EXTABLE_CPY
entries in the exception table. ex_fault_handler_type() returns
EX_HANDLER_UACCESS for both of these.
Recovery is only possible when the machine check was triggered
on a read from user memory. In this case the same strategy for
recovery applies as if the user had made the access in ring3. If
the fault was in kernel memory while copying to user there is no
current recovery plan.
For MOV and MOVZ instructions a full decode of the instruction
is done to find the source address. For MOVS instructions
the source address is in the %rsi register. The function
fault_in_kernel_space() determines whether the source address is
kernel or user, upgrade it from "static" so it can be used here.
Co-developed-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-7-tony.luck@intel.com
Existing kernel code can only recover from a machine check on code that
is tagged in the exception table with a fault handling recovery path.
Add two new fields in the task structure to pass information from
machine check handler to the "task_work" that is queued to run before
the task returns to user mode:
+ mce_vaddr: will be initialized to the user virtual address of the fault
in the case where the fault occurred in the kernel copying data from
a user address. This is so that kill_me_maybe() can provide that
information to the user SIGBUS handler.
+ mce_kflags: copy of the struct mce.kflags needed by kill_me_maybe()
to determine if mce_vaddr is applicable to this error.
Add code to recover from a machine check while copying data from user
space to the kernel. Action for this case is the same as if the user
touched the poison directly; unmap the page and send a SIGBUS to the task.
Use a new helper function to share common code between the "fault
in user mode" case and the "fault while copying from user" case.
New code paths will be activated by the next patch which sets
MCE_IN_KERNEL_COPYIN.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-6-tony.luck@intel.com
In the page fault case it is ok to see if a few more unaligned bytes
can be copied from the source address. Worst case is that the page fault
will be triggered again.
Machine checks are more serious. Just give up at the point where the
main copy loop triggered the #MC and return from the copy code as if
the copy succeeded. The machine check handler will use task_work_add() to
make sure that the task is sent a SIGBUS.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-5-tony.luck@intel.com
_ASM_EXTABLE_UA is a general exception entry to record the exception fixup
for all exception spots between kernel and user space access.
To enable recovery from machine checks while coping data from user
addresses it is necessary to be able to distinguish the places that are
looping copying data from those that copy a single byte/word/etc.
Add a new macro _ASM_EXTABLE_CPY and use it in place of _ASM_EXTABLE_UA
in the copy functions.
Record the exception reason number to regs->ax at
ex_handler_uaccess which is used to check MCE triggered.
The new fixup routine ex_handler_copy() is almost an exact copy of
ex_handler_uaccess() The difference is that it sets regs->ax to the trap
number. Following patches use this to avoid trying to copy remaining
bytes from the tail of the copy and possibly hitting the poison again.
New mce.kflags bit MCE_IN_KERNEL_COPYIN will be used by mce_severity()
calculation to indicate that a machine check is recoverable because the
kernel was copying from user space.
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-4-tony.luck@intel.com
Avoid a proliferation of ex_has_*_handler() functions by having just
one function that returns the type of the handler (if any).
Drop the __visible attribute for this function. It is not called
from assembler so the attribute is not necessary.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-3-tony.luck@intel.com
