In pcibios_alloc_controller(), 'phb' is allocated and escaped into
global 'hose_list'. So we should call of_node_get() when a new reference
created into 'phb->dn'. And when phb is freed, we should call
of_node_put() on it.
NOTE: This function is called in the iteration of for_each_xx in
chrp_find_bridges() and pSeries_discover_phbs(). If there is no
of_node_get(), the object may be prematurely freed.
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220702022936.266146-1-windhl@126.com
In these driver init functions, there are two kinds of errors:
(1) missing of_put_node() for of_find_compatible_node()'s returned
pointer (refcount incremented) in fail path or when it is not
used anymore.
(2) missing of_put_node() for 'for_each_xxx' loop's break
Signed-off-by: Liang He <windhl@126.com>
[mpe: Use out_put_xxx goto label naming]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220620132553.4073863-1-windhl@126.com
In ppc47x_init_irq(), we need to call of_node_put() when there is
a break during the iteration of for_each_node_with_property() which
will automatically increase and decrease the refcount.
Signed-off-by: Liang He <windhl@126.com>
[mpe: mpic_alloc() takes its own reference]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220701133126.243102-1-windhl@126.com
There are several bugs as following:
(1) In cbe_get_be_node(), hold the reference returned by of_find_xxx and
of_get_xxx OF APIs and use it to call of_node_put().
(2) In cbe_fill_regs_map(), same as above.
(3) In cbe_regs_init(), during the iteration of for_each_node_by_type(),
the refcount of 'cpu' will be automatically increased and decreased.
However, there is a reference escaped out into 'map->cpu_node' and
it should be properly handled.
Signed-off-by: Liang He <windhl@126.com>
[mpe: Drop references before pointer equality test in cbe_get_be_node()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220701144949.252364-1-windhl@126.com
In media5200_init_irq(), of_find_compatible_node() will return a
node pointer with refcount incremented. The reference should be dropped
with of_node_put() in the failure path or when it is not used anymore.
Don't worry about 'fpga_np == NULL' as of_node_put() can correctly
handle that.
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220616144007.3987743-1-windhl@126.com
In mpc5121_clk_init(), of_find_compatible_node() will return a
node pointer with refcount incremented. The reference should be dropped
with of_node_put() when it is not used anymore.
Signed-off-by: Liang He <windhl@126.com>
[mpe: of_clk_add_provider() will take its own reference.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220615143703.3968898-1-windhl@126.com
With recent binutils, the following warning appears:
VDSO32L arch/powerpc/kernel/vdso/vdso32.so.dbg
/opt/gcc-12.2.0-nolibc/powerpc64-linux/bin/../lib/gcc/powerpc64-linux/12.2.0/../../../../powerpc64-linux/bin/ld: warning: arch/powerpc/kernel/vdso/getcpu-32.o: missing .note.GNU-stack section implies executable stack
/opt/gcc-12.2.0-nolibc/powerpc64-linux/bin/../lib/gcc/powerpc64-linux/12.2.0/../../../../powerpc64-linux/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
To avoid that, explicitly tell the linker we don't want executable
stack.
For more explanations, see commit ffcf9c5700 ("x86: link vdso
and boot with -z noexecstack --no-warn-rwx-segments")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b95f2e3216a574837dd61208444e9515c3423da4.1662132312.git.christophe.leroy@csgroup.eu
When building with a recent version of clang, there are a couple of
errors around the call to module_init():
arch/powerpc/math-emu/math_efp.c:927:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
module_init(spe_mathemu_init);
^
int
arch/powerpc/math-emu/math_efp.c:927:13: error: a parameter list without types is only allowed in a function definition
module_init(spe_mathemu_init);
^
2 errors generated.
module_init() is a macro, which is not getting expanded because module.h
is not included in this file. Add the include so that the macro can
expand properly, clearing up the build failure.
Fixes: ac6f120369 ("powerpc/85xx: Workaroudn e500 CPU erratum A005")
[chleroy: added fixes tag]
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/8403854a4c187459b2f4da3537f51227b70b9223.1662134272.git.christophe.leroy@csgroup.eu
Distro kernels tend to be moving to VIRT_CPU_ACCOUNTING_GEN, and there
is not much reason why PPC64 should be special here. Remove the special
case and make the ppc64 and pseries defconfigs use GEN accounting
(others will use TICK, as-per Kconfig defaults).
VIRT_CPU_ACCOUNTING_NATIVE does provide scaled vtime and stolen time
apportioned between system and user time, and vtime accounting is not
unconditionally enabled, and possibly other things. But it would be
better at this point to extend GEN to cover important missing features
rather than directing users back to a less used option.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220902085316.2071519-4-npiggin@gmail.com
CONFIG_VIRT_CPU_ACCOUNTING_GEN under pseries does not provide stolen
time accounting unless CONFIG_PARAVIRT_TIME_ACCOUNTING is enabled.
Implement this using the VPA accumulated wait counters.
Note this will not work on current KVM hosts because KVM does not
implement the VPA dispatch counters (yet). It could be implemented
with the dispatch trace log as it is for VIRT_CPU_ACCOUNTING_NATIVE,
but that is not necessary for the more limited accounting provided
by PARAVIRT_TIME_ACCOUNTING, and it is more expensive, complex, and
has downsides like potential log wrap.
From Shrikanth:
[...] it was tested on Power10 [PowerVM] Shared LPAR. system has two
LPAR. we will call first one LPAR1 and second one as LPAR2. Test was
carried out in SMT=1. Similar observation was seen in SMT=8 as well.
LPAR config header from each LPAR is below. LPAR1 is twice as big as
LPAR2. Since Both are sharing the same underlying hardware, work
stealing will happen when both the LPAR's are contending for the same
resource.
LPAR1:
type=Shared mode=Uncapped smt=Off lcpu=40 cpus=40 ent=20.00
LPAR2:
type=Shared mode=Uncapped smt=Off lcpu=20 cpus=40 ent=10.00
mpstat was used to check for the utilization. stress-ng has been used
as the workload. Few cases are tested. when the both LPAR are idle
there is no steal time. when LPAR1 starts running at 100% which
consumes all of the physical resource, steal time starts to get
accounted. With LPAR1 running at 100% and LPAR2 starts running, steal
time starts increasing. This is as expected. When the LPAR2 Load is
increased further, steal time increases further.
Case 1: 0% LPAR1; 0% LPAR2
%usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle
0.00 0.00 0.05 0.00 0.00 0.00 0.00 0.00 0.00 99.95
Case 2: 100% LPAR1; 0% LPAR2
%usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle
97.68 0.00 0.00 0.00 0.00 0.00 2.32 0.00 0.00 0.00
Case 3: 100% LPAR1; 50% LPAR2
%usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle
86.34 0.00 0.10 0.00 0.00 0.03 13.54 0.00 0.00 0.00
Case 4: 100% LPAR1; 100% LPAR2
%usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle
78.54 0.00 0.07 0.00 0.00 0.02 21.36 0.00 0.00 0.00
Case 5: 50% LPAR1; 100% LPAR2
%usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle
49.37 0.00 0.00 0.00 0.00 0.00 1.17 0.00 0.00 49.47
Patch is accounting for the steal time and basic tests are holding
good.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
[mpe: Add SPDX tag to new paravirt_api_clock.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220902085316.2071519-3-npiggin@gmail.com
Since commit 591b4b2684 ("powerpc/code-patching: Pre-map patch area")
the patch area is premapped so intermediate page tables are already
allocated.
Use __set_pte_at() directly instead of the heavy map_kernel_page(),
at for unmapping just do a pte_clear() followed by a flush.
__set_pte_at() can be used directly without the filters in
set_pte_at() because we are mapping a normal page non executable.
Make sure gcc knows text_poke_area is page aligned in order to
optimise the flush.
This change reduces by 66% the time needed to activate ftrace on
an 8xx (588000 tb ticks instead of 1744000).
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Add ptesync needed on radix to avoid spurious fault]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220815114840.1468656-1-mpe@ellerman.id.au
Add support for execute-only memory (XOM) for the Radix MMU by using an
execute-only mapping, as opposed to the RX mapping used by powerpc's
other MMUs.
The Hash MMU already supports XOM through the execute-only pkey,
which is a separate mechanism shared with x86. A PROT_EXEC-only mapping
will map to RX, and then the pkey will be applied on top of it.
mmap() and mprotect() consumers in userspace should observe the same
behaviour on Hash and Radix despite the differences in implementation.
Replacing the vma_is_accessible() check in access_error() with a read
check should be functionally equivalent for non-Radix MMUs, since it
follows write and execute checks. For Radix, the change enables
detecting faults on execute-only mappings where vma_is_accessible() would
return true.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220817050640.406017-1-ruscur@russell.cc
