Right now 'char *' elements allocated for individual 'stat_id' in
'papr_scm_priv.nvdimm_events_map[]' during papr_scm_pmu_check_events(), get
leaked in papr_scm_remove() and papr_scm_pmu_register(),
papr_scm_pmu_check_events() error paths.
Also individual 'stat_id' arent NULL terminated 'char *' instead they are fixed
8-byte sized identifiers. However papr_scm_pmu_register() assumes it to be a
NULL terminated 'char *' and at other places it assumes it to be a
'papr_scm_perf_stat.stat_id' sized string which is 8-byes in size.
Fix this by allocating the memory for papr_scm_priv.nvdimm_events_map to also
include space for 'stat_id' entries. This is possible since number of available
events/stat_ids are known upfront. This saves some memory and one extra level of
indirection from 'nvdimm_events_map' to 'stat_id'. Also rest of the code
can continue to call 'kfree(papr_scm_priv.nvdimm_events_map)' without needing to
iterate over the array and free up individual elements.
Fixes: 4c08d4bbc0 ("powerpc/papr_scm: Add perf interface support")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220511082637.646714-1-vaibhav@linux.ibm.com
powerpc is the only platform that do not rely on
cpu_up()->try_online_node() to bring up a numa node,
and special cases it, instead, deep in its own machinery:
dlpar_online_cpu
find_and_online_cpu_nid
try_online_node
This should not be needed, but the thing is that the try_online_node()
from cpu_up() will not apply on the right node, because cpu_to_node()
will return the old mapping numa<->cpu that gets set on boot stage
for all possible cpus.
That can be seen easily if we try to print out the numa node passed
to try_online_node() in cpu_up().
The thing is that the numa<->cpu mapping does not get updated till a much
later stage in start_secondary:
start_secondary:
set_numa_node(numa_cpu_lookup_table[cpu])
But we do not really care, as we already now the
CPU <-> NUMA associativity back in find_and_online_cpu_nid(),
so let us make use of that and set the proper numa<->cpu mapping,
so cpu_to_node() in cpu_up() returns the right node and
try_online_node() can do its work.
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Geetika Moolchandani <Geetika.Moolchandani1@ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220411074934.4632-1-osalvador@suse.de
Implement a limited form of KASAN for Book3S 64-bit machines running under
the Radix MMU, supporting only outline mode.
- Enable the compiler instrumentation to check addresses and maintain the
shadow region. (This is the guts of KASAN which we can easily reuse.)
- Require kasan-vmalloc support to handle modules and anything else in
vmalloc space.
- KASAN needs to be able to validate all pointer accesses, but we can't
instrument all kernel addresses - only linear map and vmalloc. On boot,
set up a single page of read-only shadow that marks all iomap and
vmemmap accesses as valid.
- Document KASAN in powerpc docs.
Background
----------
KASAN support on Book3S is a bit tricky to get right:
- It would be good to support inline instrumentation so as to be able to
catch stack issues that cannot be caught with outline mode.
- Inline instrumentation requires a fixed offset.
- Book3S runs code with translations off ("real mode") during boot,
including a lot of generic device-tree parsing code which is used to
determine MMU features.
[ppc64 mm note: The kernel installs a linear mapping at effective
address c000...-c008.... This is a one-to-one mapping with physical
memory from 0000... onward. Because of how memory accesses work on
powerpc 64-bit Book3S, a kernel pointer in the linear map accesses the
same memory both with translations on (accessing as an 'effective
address'), and with translations off (accessing as a 'real
address'). This works in both guests and the hypervisor. For more
details, see s5.7 of Book III of version 3 of the ISA, in particular
the Storage Control Overview, s5.7.3, and s5.7.5 - noting that this
KASAN implementation currently only supports Radix.]
- Some code - most notably a lot of KVM code - also runs with translations
off after boot.
- Therefore any offset has to point to memory that is valid with
translations on or off.
One approach is just to give up on inline instrumentation. This way
boot-time checks can be delayed until after the MMU is set is up, and we
can just not instrument any code that runs with translations off after
booting. Take this approach for now and require outline instrumentation.
Previous attempts allowed inline instrumentation. However, they came with
some unfortunate restrictions: only physically contiguous memory could be
used and it had to be specified at compile time. Maybe we can do better in
the future.
[paulus@ozlabs.org - Rebased onto 5.17. Note that a kernel with
CONFIG_KASAN=y will crash during boot on a machine using HPT
translation because not all the entry points to the generic
KASAN code are protected with a call to kasan_arch_is_ready().]
Originally-by: Balbir Singh <bsingharora@gmail.com> # ppc64 out-of-line radix version
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Update copyright year and comment formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/YoTE69OQwiG7z+Gu@cleo
The kexec code paths involve code that necessarily run in real mode, as
CPUs are disabled and control is transferred to the new kernel. Disable
address sanitization for the kexec code and the functions called in real
mode on CPUs being disabled.
[paulus@ozlabs.org: combined a few work-in-progress commits of
Daniel's and wrote the commit message.]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Move pseries_machine_kexec() into kexec.c so setup.c can be instrumented]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/YoTFSQ2TUSEaDdVC@cleo
Disable address sanitization for raw and non-maskable interrupt
handlers, because they can run in real mode, where we cannot access
the shadow memory. (Note that kasan_arch_is_ready() doesn't test for
real mode, since it is a static branch for speed, and in any case not
all the entry points to the generic KASAN code are protected by
kasan_arch_is_ready guards.)
The changes to interrupt_nmi_enter/exit_prepare() look larger than
they actually are. The changes are equivalent to adding
!IS_ENABLED(CONFIG_KASAN) to the conditions for calling nmi_enter() or
nmi_exit() in real mode. That is, the code is equivalent to using the
following condition for calling nmi_enter/exit:
if (((!IS_ENABLED(CONFIG_PPC_BOOK3S_64) ||
!firmware_has_feature(FW_FEATURE_LPAR) ||
radix_enabled()) &&
!IS_ENABLED(CONFIG_KASAN) ||
(mfmsr() & MSR_DR))
That unwieldy condition has been split into several statements with
comments, for easier reading.
The nmi_ipi_lock functions that call atomic functions (i.e.,
nmi_ipi_lock_start(), nmi_ipi_lock() and nmi_ipi_unlock()), besides
being marked noinstr, now call arch_atomic_* functions instead of
atomic_* functions because with KASAN enabled, the atomic_* functions
are wrappers which explicitly do address sanitization on their
arguments. Since we are trying to avoid address sanitization, we have
to use the lower-level arch_atomic_* versions.
In hv_nmi_check_nonrecoverable(), the regs_set_unrecoverable() call
has been open-coded so as to avoid having to either trust the inlining
or mark regs_set_unrecoverable() as noinstr.
[paulus@ozlabs.org: combined a few work-in-progress commits of
Daniel's and wrote the commit message.]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/YoTFGaKM8Pd46PIK@cleo
The device-tree property no-need-store-drain-on-priv-state-switch is
equivalent to H_CPU_BEHAV_NO_STF_BARRIER from the
H_CPU_GET_CHARACTERISTICS hcall on pseries.
Since commit 84ed26fd00 ("powerpc/security: Add a security feature for
STF barrier") powernv systems with this device-tree property have been
enabling the STF barrier when they have no need for it. This patch
fixes this by clearing the STF barrier feature on those systems.
Fixes: 84ed26fd00 ("powerpc/security: Add a security feature for STF barrier")
Reported-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220404101536.104794-2-ruscur@russell.cc
The device-tree properties no-need-l1d-flush-msr-pr-1-to-0 and
no-need-l1d-flush-kernel-on-user-access are the equivalents of
H_CPU_BEHAV_NO_L1D_FLUSH_ENTRY and H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS
from the H_GET_CPU_CHARACTERISTICS hcall on pseries respectively.
In commit d02fa40d75 ("powerpc/powernv: Remove POWER9 PVR version
check for entry and uaccess flushes") the condition for disabling the
L1D flush on kernel entry and user access was changed from any non-P9
CPU to only checking P7 and P8. Without the appropriate device-tree
checks for newer processors on powernv, these flushes are unnecessarily
enabled on those systems. This patch corrects this.
Fixes: d02fa40d75 ("powerpc/powernv: Remove POWER9 PVR version check for entry and uaccess flushes")
Reported-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220404101536.104794-1-ruscur@russell.cc
In init_winctx_regs(), __pa() is called on winctx->rx_fifo and this
function is called to initialize registers for receive and fault
windows. But the real address is passed in winctx->rx_fifo for
receive windows and the virtual address for fault windows which
causes errors with DEBUG_VIRTUAL enabled. Fixes this issue by
assigning only real address to rx_fifo in vas_rx_win_attr struct
for both receive and fault windows.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/338e958c7ab8f3b266fa794a1f80f99b9671829e.camel@linux.ibm.com
LoPAPR defines guest visible IOMMU with hypercalls to use it -
H_PUT_TCE/etc. Implemented first on POWER7 where hypercalls would trap
in the KVM in the real mode (with MMU off). The problem with the real mode
is some memory is not available and some API usage crashed the host but
enabling MMU was an expensive operation.
The problems with the real mode handlers are:
1. Occasionally these cannot complete the request so the code is
copied+modified to work in the virtual mode, very little is shared;
2. The real mode handlers have to be linked into vmlinux to work;
3. An exception in real mode immediately reboots the machine.
If the small DMA window is used, the real mode handlers bring better
performance. However since POWER8, there has always been a bigger DMA
window which VMs use to map the entire VM memory to avoid calling
H_PUT_TCE. Such 1:1 mapping happens once and uses H_PUT_TCE_INDIRECT
(a bulk version of H_PUT_TCE) which virtual mode handler is even closer
to its real mode version.
On POWER9 hypercalls trap straight to the virtual mode so the real mode
handlers never execute on POWER9 and later CPUs.
So with the current use of the DMA windows and MMU improvements in
POWER9 and later, there is no point in duplicating the code.
The 32bit passed through devices may slow down but we do not have many
of these in practice. For example, with this applied, a 1Gbit ethernet
adapter still demostrates above 800Mbit/s of actual throughput.
This removes the real mode handlers from KVM and related code from
the powernv platform.
This updates the list of implemented hcalls in KVM-HV as the realmode
handlers are removed.
This changes ABI - kvmppc_h_get_tce() moves to the KVM module and
kvmppc_find_table() is static now.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220506053755.3820702-1-aik@ozlabs.ru
With CONFIG_FORTIFY_SOURCE enabled, string functions will also perform
dynamic checks for string size which can panic the kernel, like incase
of overflow detection.
In papr_scm, papr_scm_pmu_check_events function uses stat->stat_id with
string operations, to populate the nvdimm_events_map array. Since
stat_id variable is not NULL terminated, the kernel panics with
CONFIG_FORTIFY_SOURCE enabled at boot time.
Below are the logs of kernel panic:
detected buffer overflow in __fortify_strlen
------------[ cut here ]------------
kernel BUG at lib/string_helpers.c:980!
Oops: Exception in kernel mode, sig: 5 [#1]
NIP [c00000000077dad0] fortify_panic+0x28/0x38
LR [c00000000077dacc] fortify_panic+0x24/0x38
Call Trace:
[c0000022d77836e0] [c00000000077dacc] fortify_panic+0x24/0x38 (unreliable)
[c00800000deb2660] papr_scm_pmu_check_events.constprop.0+0x118/0x220 [papr_scm]
[c00800000deb2cb0] papr_scm_probe+0x288/0x62c [papr_scm]
[c0000000009b46a8] platform_probe+0x98/0x150
Fix this issue by using kmemdup_nul() to copy the content of
stat->stat_id directly to the nvdimm_events_map array.
mpe: stat->stat_id comes from the hypervisor, not userspace, so there is
no security exposure.
Fixes: 4c08d4bbc0 ("powerpc/papr_scm: Add perf interface support")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220505153451.35503-1-kjain@linux.ibm.com
The user can change the QoS credits dynamically with the
management console interface which notifies OS with sysfs. After
returning from the OS interface successfully, the management
console updates the hypervisor. Since the VAS capabilities in
the hypervisor is not updated when the OS gets the update,
the kernel is using the old total credits value from the
hypervisor. Fix this issue by using the new QoS credits
from the userspace instead of depending on VAS capabilities
from the hypervisor.
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/76d156f8af1e03cc09369d68e0bfad0c40031bcc.camel@linux.ibm.com
__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.
A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) argument or environment
strings.
Also, error return codes don't mean anything to obsolete_checksetup() --
only non-zero (usually 1) or zero. So return 1 from cpm_powersave_off().
Fixes: d164f6d4f9 ("powerpc/4xx: Add suspend and idle support")
Reported-by: Igor Zhbanov <izh1979@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220502192941.20955-1-rdunlap@infradead.org
The strlcpy should not be used because it doesn't limit the source
length. As linus says, it's a completely useless function if you
can't implicitly trust the source string - but that is almost always
why people think they should use it! All in all the BSD function
will lead some potential bugs.
But the strscpy doesn't require reading memory from the src string
beyond the specified "count" bytes, and since the return value is
easier to error-check than strlcpy()'s. In addition, the implementation
is robust to the string changing out from underneath it, unlike the
current strlcpy() implementation.
Thus, We prefer using strscpy instead of strlcpy.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210807072154.64512-1-wangborong@cdjrlc.com
Fix some pr_debug() issues in mpc52xx_pci.c:
- use __func__ to print function names
- use "%pr" to print struct resource entries
- use "%pa" to print a resource_size_t (phys_addr_t)
The latter two fix several build warnings:
../arch/powerpc/platforms/52xx/mpc52xx_pci.c: In function 'mpc52xx_pci_setup':
../include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 2 has type 'resource_size_t' {aka 'long long unsigned int'} [-Wformat=]
../arch/powerpc/platforms/52xx/mpc52xx_pci.c:277:40: note: format string is defined here
277 | pr_debug("mem_resource[1] = {.start=%x, .end=%x, .flags=%lx}\n",
| ~^
| |
| unsigned int
| %llx
../include/linux/kern_levels.h:5:18: warning: format '%x' expects argument of type 'unsigned int', but argument 3 has type 'resource_size_t' {aka 'long long unsigned int'} [-Wformat=]
../arch/powerpc/platforms/52xx/mpc52xx_pci.c:277:49: note: format string is defined here
277 | pr_debug("mem_resource[1] = {.start=%x, .end=%x, .flags=%lx}\n",
| ~^
| |
| unsigned int
| %llx
../arch/powerpc/platforms/52xx/mpc52xx_pci.c:299:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
299 | (unsigned long long)res->flags, (void*)hose->io_base_phys);
| ^
../arch/powerpc/platforms/52xx/mpc52xx_pci.c:295:2: note: in expansion of macro 'pr_debug'
295 | pr_debug(".io_resource={.start=%llx,.end=%llx,.flags=%llx} "
| ^~~~~~~~
The change to print mem_resource[0] is for consistency within this
source file and to use the kernel API -- there were no warnings here.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
[chleroy: Fixed checkpatch complaints]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210429005323.8195-1-rdunlap@infradead.org
We found these warnings in arch/powerpc/kernel/time.c as follows:
warning: symbol 'decrementer_max' was not declared. Should it be static?
warning: symbol 'rtc_lock' was not declared. Should it be static?
warning: symbol 'dtl_consumer' was not declared. Should it be static?
Declare 'decrementer_max' in powerpc asm/time.h.
Include linux/mc146818rtc.h in powerpc kernel/time.c where 'rtc_lock' is
declared. And remove duplicated declaration of 'rtc_lock' in powerpc
platforms/chrp/time.c because it has included linux/mc146818rtc.h.
Move 'dtl_consumer' definition after "include <asm/dtl.h>" because it is
declared there.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210324090939.143477-1-heying24@huawei.com
In smp_85xx_start_cpu() we are passed an address but we're unsure if
it's a real or virtual address, so there's a check to determine that.
The check has an off-by-one in that it tests if the address is greater
than high_memory, but high_memory is the first address of high memory,
so the check should be greater-or-equal.
It seems this has never been a problem in practice, but it also triggers
the DEBUG_VIRTUAL checks in __pa() which we would like to avoid. We can
fix both issues by converting high_memory - 1 to a physical address and
testing against that.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220406145802.538416-3-mpe@ellerman.id.au
On crash, boot memory area is copied to a destination address by f/w.
This region is setup as separate PT_LOAD segment with appropriate
offset to handle the different physical address and offset in vmcore.
If this destination address is not page aligned, reading the vmcore
with mmap is likely to fail forcing tools like makedumpfile to fall
back to regular read. Avoid mmap read failure by ensuring that the
destination address is always page aligned.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220406093839.206608-3-hbathini@linux.ibm.com
An LPAR can be terminated by the POWER Hypervisor (PHYP) for various
reasons. If FADump was configured when PHYP terminates the LPAR,
platform-assisted dump is initiated to save the kernel dump. But CPU
register data would not be processed/saved in the vmcore in such case
because CPU mask is set in crash_fadump() at the time of kernel crash
and it remains unset in this case with LPAR being terminated by PHYP
abruptly.
To get around the problem, initialize cpu_mask to cpu_possible_mask
so as to ensure all possible CPUs' register data is processed for the
vmcore generated on PHYP terminated LPAR. Also, rename the crash info
member variable from online_mask to cpu_mask as it doesn't necessarily
have to be online CPU mask always.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220404182137.59231-1-hbathini@linux.ibm.com
Dump capture would fail if capture kernel is not of the endianess as the
production kernel, because the in-memory data structure (struct
opal_fadump_mem_struct) shared across production kernel and capture
kernel assumes the same endianess for both the kernels, which doesn't
have to be true always. Fix it by having a well-defined endianess for
struct opal_fadump_mem_struct.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161902744901.86147.14719228311655123526.stgit@hbathini
Pull driver core updates from Greg KH:
"Here are two small driver core changes for 5.18-rc2.
They are the final bits in the removal of the default_attrs field in
struct kobj_type. I had to wait until after 5.18-rc1 for all of the
changes to do this came in through different development trees, and
then one new user snuck in. So this series has two changes:
- removal of the default_attrs field in the powerpc/pseries/vas code.
The change has been acked by the PPC maintainers to come through
this tree
- removal of default_attrs from struct kobj_type now that all
in-kernel users are removed.
This cleans up the kobject code a little bit and removes some
duplicated functionality that confused people (now there is only
one way to do default groups)
Both of these have been in linux-next for all of this week with no
reported problems"
* tag 'driver-core-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kobject: kobj_type: remove default_attrs
powerpc/pseries/vas: use default_groups in kobj_type
