Implement the barrier_nospec as a isync;sync instruction sequence.
The implementation uses the infrastructure built for BOOK3S 64.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently we require platform code to call setup_barrier_nospec(). But
if we add an empty definition for the !CONFIG_PPC_BARRIER_NOSPEC case
then we can call it in setup_arch().
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add a config symbol to encode which platforms support the
barrier_nospec speculation barrier. Currently this is just Book3S 64
but we will add Book3E in a future patch.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We pass the "loc" (location) parameter to MASKABLE_EXCEPTION and
friends, but it's not used, so drop it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
_MASKABLE_RELON_EXCEPTION_PSERIES() does nothing useful, update all
callers to use __MASKABLE_RELON_EXCEPTION_PSERIES() directly.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
_MASKABLE_EXCEPTION_PSERIES() does nothing useful, update all callers
to use __MASKABLE_EXCEPTION_PSERIES() directly.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The EXCEPTION_RELON_PROLOG_PSERIES_1() macro does the same job as
EXCEPTION_PROLOG_2 (which we just recently created), except for
"RELON" (relocation on) exceptions.
So rename it as such.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As with the other patches in this series, we are removing the
"PSERIES" from the name as it's no longer meaningful.
In this case it's not simply a case of removing the "PSERIES" as that
would result in a clash with the existing EXCEPTION_PROLOG_1.
Instead we name this one EXCEPTION_PROLOG_2, as it's usually used in
sequence after 0 and 1.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The "PSERIES" in STD_EXCEPTION_PSERIES is to differentiate the macros
from the legacy iSeries versions, which are called
STD_EXCEPTION_ISERIES. It is not anything to do with pseries vs
powernv or powermac etc.
We removed the legacy iSeries code in 2012, in commit 8ee3e0d69623x
("powerpc: Remove the main legacy iSerie platform code").
So remove "PSERIES" from the macros.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
EXCEPTION_RELON_PROLOG_PSERIES() only has two users,
STD_RELON_EXCEPTION_PSERIES() and STD_RELON_EXCEPTION_HV() both of
which "call" SET_SCRATCH0(), so just move SET_SCRATCH0() into
EXCEPTION_RELON_PROLOG_PSERIES().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
EXCEPTION_PROLOG_PSERIES() only has two users, STD_EXCEPTION_PSERIES()
and STD_EXCEPTION_HV() both of which "call" SET_SCRATCH0(), so just
move SET_SCRATCH0() into EXCEPTION_PROLOG_PSERIES().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The generic implementation of strlen() reads strings byte per byte.
This patch implements strlen() in assembly based on a read of entire
words, in the same spirit as what some other arches and glibc do.
On a 8xx the time spent in strlen is reduced by 3/4 for long strings.
strlen() selftest on an 8xx provides the following values:
Before the patch (ie with the generic strlen() in lib/string.c):
len 256 : time = 1.195055
len 016 : time = 0.083745
len 008 : time = 0.046828
len 004 : time = 0.028390
After the patch:
len 256 : time = 0.272185 ==> 78% improvment
len 016 : time = 0.040632 ==> 51% improvment
len 008 : time = 0.033060 ==> 29% improvment
len 004 : time = 0.029149 ==> 2% degradation
On a 832x:
Before the patch:
len 256 : time = 0.236125
len 016 : time = 0.018136
len 008 : time = 0.011000
len 004 : time = 0.007229
After the patch:
len 256 : time = 0.094950 ==> 60% improvment
len 016 : time = 0.013357 ==> 26% improvment
len 008 : time = 0.010586 ==> 4% improvment
len 004 : time = 0.008784
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
rtas_log_buf is a buffer to hold RTAS event data that are communicated
to kernel by hypervisor. This buffer is then used to pass RTAS event
data to user through proc fs. This buffer is allocated from
vmalloc (non-linear mapping) area.
On Machine check interrupt, register r3 points to RTAS extended event
log passed by hypervisor that contains the MCE event. The pseries
machine check handler then logs this error into rtas_log_buf. The
rtas_log_buf is a vmalloc-ed (non-linear) buffer we end up taking up a
page fault (vector 0x300) while accessing it. Since machine check
interrupt handler runs in NMI context we can not afford to take any
page fault. Page faults are not honored in NMI context and causes
kernel panic. Apart from that, as Nick pointed out,
pSeries_log_error() also takes a spin_lock while logging error which
is not safe in NMI context. It may endup in deadlock if we get another
MCE before releasing the lock. Fix this by deferring the logging of
rtas error to irq work queue.
Current implementation uses two different buffers to hold rtas error
log depending on whether extended log is provided or not. This makes
bit difficult to identify which buffer has valid data that needs to
logged later in irq work. Simplify this using single buffer, one per
paca, and copy rtas log to it irrespective of whether extended log is
provided or not. Allocate this buffer below RMA region so that it can
be accessed in real mode mce handler.
Fixes: b96672dd84 ("powerpc: Machine check interrupt is a non-maskable interrupt")
Cc: stable@vger.kernel.org # v4.14+
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It's identical to xive_teardown_cpu() so just use the latter
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When the mm is being torn down there will be a full PID flush so
there is no need to flush the TLB on page size changes.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Adds support to enable/disable a sensor group at runtime. This
can be used to select the sensor groups that needs to be copied to
main memory by OCC. Sensor groups like power, temperature, current,
voltage, frequency, utilization can be enabled/disabled at runtime.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Export pnv_idle_states and nr_pnv_idle_states so that its accessible to
cpuidle driver. Use properties from pnv_idle_states structure for powernv
cpuidle_init.
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Device-tree parsing happens twice, once while deciding idle state to be
used for hotplug and once during cpuidle init. Hence, parsing the device
tree and caching it will reduce code duplication. Parsing code has been
moved to pnv_parse_cpuidle_dt() from pnv_probe_idle_states(). In addition
to the properties in the device tree the number of available states is
also required.
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Paul Menzel reported that kmemleak was producing reports such as:
unreferenced object 0xc0000000f8b80000 (size 16384):
comm "init", pid 1, jiffies 4294937416 (age 312.240s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000d997deb7>] __pud_alloc+0x80/0x190
[<0000000087f2e8a3>] move_page_tables+0xbac/0xdc0
[<00000000091e51c2>] shift_arg_pages+0xc0/0x210
[<00000000ab88670c>] setup_arg_pages+0x22c/0x2a0
[<0000000060871529>] load_elf_binary+0x41c/0x1648
[<00000000ecd9d2d4>] search_binary_handler.part.11+0xbc/0x280
[<0000000034e0cdd7>] __do_execve_file.isra.13+0x73c/0x940
[<000000005f953a6e>] sys_execve+0x58/0x70
[<000000009700a858>] system_call+0x5c/0x70
Indicating that a PUD was being leaked.
However what's really happening is that kmemleak is not able to
recognise the references from the PGD to the PUD, because they are not
fully qualified pointers.
We can confirm that in xmon, eg:
Find the task struct for pid 1 "init":
0:mon> P
task_struct ->thread.ksp PID PPID S P CMD
c0000001fe7c0000 c0000001fe803960 1 0 S 13 systemd
Dump virtual address 0 to find the PGD:
0:mon> dv 0 c0000001fe7c0000
pgd @ 0xc0000000f8b01000
Dump the memory of the PGD:
0:mon> d c0000000f8b01000
c0000000f8b01000 00000000f8b90000 0000000000000000 |................|
c0000000f8b01010 0000000000000000 0000000000000000 |................|
c0000000f8b01020 0000000000000000 0000000000000000 |................|
c0000000f8b01030 0000000000000000 00000000f8b80000 |................|
^^^^^^^^^^^^^^^^
There we can see the reference to our supposedly leaked PUD. But
because it's missing the leading 0xc, kmemleak won't recognise it.
We can confirm it's still in use by translating an address that is
mapped via it:
0:mon> dv 7fff94000000 c0000001fe7c0000
pgd @ 0xc0000000f8b01000
pgdp @ 0xc0000000f8b01038 = 0x00000000f8b80000 <--
pudp @ 0xc0000000f8b81ff8 = 0x00000000037c4000
pmdp @ 0xc0000000037c5ca0 = 0x00000000fbd89000
ptep @ 0xc0000000fbd89000 = 0xc0800001d5ce0386
Maps physical address = 0x00000001d5ce0000
Flags = Accessed Dirty Read Write
The fix is fairly simple. We need to tell kmemleak to ignore PUD
allocations and never report them as leaks. We can also tell it not to
scan the PGD, because it will never find pointers in there. However it
will still notice if we allocate a PGD and then leak it.
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
asm/tlbflush.h is only needed for:
- using functions xxx_flush_tlb_xxx()
- using MMU_NO_CONTEXT
- including asm-generic/pgtable.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
mmu-44x.h doesn't need asm/page.h if PAGE_SHIFT are replaced by CONFIG_PPC_XX_PAGES
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Remove superflous includes and add missing ones
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PPC_PIN_SIZE is specific to the 44x and is defined in mmu.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
set_breakpoint() is only used in process.c so make it static
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Files not using fixmap consts or functions don't need asm/fixmap.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
files not using feature fixup don't need asm/feature-fixups.h
files using feature fixup need asm/feature-fixups.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Only include linux/stringify.h is files using __stringify()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Files not using cpu_has_feature() don't need cpu_has_feature.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The RAW console does not need writes to be atomic, so relax
opal_put_chars to be able to do partial writes, and implement an
_atomic variant which does not take a spinlock. This API is used
in xmon, so the less locking that is used, the better chance there
is that a crash can be debugged.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
A new console flushing firmware API was introduced to replace event
polling loops, and implemented in opal-kmsg with affddff69c
("powerpc/powernv: Add a kmsg_dumper that flushes console output on
panic"), to flush the console in the panic path.
The OPAL console driver has other situations where interrupts are off
and it needs to flush the console synchronously. These still use a
polling loop.
So move the opal-kmsg flush code to opal_flush_console, and use the
new function in opal-kmsg and opal_put_chars.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch add VMX primitives to do memcmp() in case the compare size
is equal or greater than 4K bytes. KSM feature can benefit from this.
Test result with following test program(replace the "^>" with ""):
------
># cat tools/testing/selftests/powerpc/stringloops/memcmp.c
>#include <malloc.h>
>#include <stdlib.h>
>#include <string.h>
>#include <time.h>
>#include "utils.h"
>#define SIZE (1024 * 1024 * 900)
>#define ITERATIONS 40
int test_memcmp(const void *s1, const void *s2, size_t n);
static int testcase(void)
{
char *s1;
char *s2;
unsigned long i;
s1 = memalign(128, SIZE);
if (!s1) {
perror("memalign");
exit(1);
}
s2 = memalign(128, SIZE);
if (!s2) {
perror("memalign");
exit(1);
}
for (i = 0; i < SIZE; i++) {
s1[i] = i & 0xff;
s2[i] = i & 0xff;
}
for (i = 0; i < ITERATIONS; i++) {
int ret = test_memcmp(s1, s2, SIZE);
if (ret) {
printf("return %d at[%ld]! should have returned zero\n", ret, i);
abort();
}
}
return 0;
}
int main(void)
{
return test_harness(testcase, "memcmp");
}
------
Without this patch (but with the first patch "powerpc/64: Align bytes
before fall back to .Lshort in powerpc64 memcmp()." in the series):
4.726728762 seconds time elapsed ( +- 3.54%)
With VMX patch:
4.234335473 seconds time elapsed ( +- 2.63%)
There is ~+10% improvement.
Testing with unaligned and different offset version (make s1 and s2 shift
random offset within 16 bytes) can archieve higher improvement than 10%..
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Some old tool chains don't know about instructions like vcmpequd.
This patch adds .long macro for vcmpequd and vcmpequb, which is
a preparation to optimize ppc64 memcmp with VMX instructions.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We do this only with VMEMMAP config so that our page_to_[nid/section] etc are not
impacted.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There is an asynchronous aspect to smp_send_nmi_ipi. The caller waits
for all CPUs to call in to the handler, but it does not wait for
completion of the handler. This is a needless complication, so remove
it and always wait synchronously.
The synchronous wait allows the caller to easily time out and clear
the wait for completion (zero nmi_ipi_busy_count) in the case of badly
behaved handlers. This would have prevented the recent smp_send_stop
NMI IPI bug from causing the system to hang.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When the masked interrupt handler clears MSR[EE] for an interrupt in
the PACA_IRQ_MUST_HARD_MASK set, it does not set PACA_IRQ_HARD_DIS.
This makes them get out of synch.
With that taken into account, it's only low level irq manipulation
(and interrupt entry before reconcile) where they can be out of synch.
This makes the code less surprising.
It also allows the IRQ replay code to rely on the IRQ_HARD_DIS value
and not have to mtmsrd again in this case (e.g., for an external
interrupt that has been masked). The bigger benefit might just be
that there is not such an element of surprise in these two bits of
state.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Applications need the ability to associate an address-range with some
key and latter revert to its initial default key. Pkey-0 comes close to
providing this function but falls short, because the current
implementation disallows applications to explicitly associate pkey-0 to
the address range.
Lets make pkey-0 less special and treat it almost like any other key.
Thus it can be explicitly associated with any address range, and can be
freed. This gives the application more flexibility and power. The
ability to free pkey-0 must be used responsibily, since pkey-0 is
associated with almost all address-range by default.
Even with this change pkey-0 continues to be slightly more special
from the following point of view.
(a) it is implicitly allocated.
(b) it is the default key assigned to any address-range.
(c) its permissions cannot be modified by userspace.
NOTE: (c) is specific to powerpc only. pkey-0 is associated by default
with all pages including kernel pages, and pkeys are also active in
kernel mode. If any permission is denied on pkey-0, the kernel running
in the context of the application will be unable to operate.
Tested on powerpc.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Drop #define PKEY_0 0 in favour of plain old 0]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Key allocation and deallocation has the side effect of programming the
UAMOR/AMR/IAMR registers. This is wrong, since its the responsibility of
the application and not that of the kernel, to modify the permission on
the key.
Do not modify the pkey registers at key allocation/deallocation.
This patch also fixes a bug where a sys_pkey_free() resets the UAMOR
bits of the key, thus making its permissions unmodifiable from user
space. Later if the same key gets reallocated from a different thread
this thread will no longer be able to change the permissions on the key.
Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
