In mpc5xxx_fwnode_get_bus_frequency(), we should add
fwnode_handle_put() when break out of the iteration
fwnode_for_each_parent_node() as it will automatically
increase and decrease the refcounter.
Fixes: de06fba62a ("powerpc/mpc5xxx: Switch mpc5xxx_get_bus_frequency() to use fwnode")
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230322030423.1855440-1-windhl@126.com
In 5.10 commit 5e84dd547b ("powerpc/configs/skiroot: Enable some more
hardening options") set SLUB_DEBUG_ON.
When 5.14 came around, commit 792702911f ("slub: force on
no_hash_pointers when slub_debug is enabled") print all the
pointers when SLUB_DEBUG_ON is set. This was fine, but in 5.12 commit
5ead723a20 ("lib/vsprintf: no_hash_pointers prints all addresses as
unhashed") added the warning at boot.
Disable SLAB_DEBUG_ON as we don't want the nasty warning. We have
CONFIG_EXPERT so SLAB_DEBUG is enabled. We do lose the settings in
DEBUG_DEFAULT_FLAGS, but it's not clear that these should have been
always-on anyway.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230705023056.16273-1-joel@jms.id.au
When JUMP_LABEL=n, the tracepoint refcount test in the pre-call stores
the refcount value to the stack, so the same value can be used for the
post-call (presumably to avoid racing with the value concurrently
changing).
On little-endian (ELFv2) that might have just worked by luck, because
32(r1) is STK_PARAM(R3) there and so the value save gets clobbered by
the tracing code when it's non-zero, but fortunately r3 is the hcall
number and 0 is an invalid hcall number so it should get clobbered by
another non-zero value. In any case, commit cc1adb5f32
("powerpc/pseries: Use jump labels for hcall tracepoints") removed the
code that actually used the value stored, so now it's just dead code.
It's fragile to be storing to the stack like this, and confusing. Better
remove it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230509091600.70994-2-npiggin@gmail.com
Currently the -mtune options are set in the Makefile, depending on what
the compiler supports.
One downside of doing it that way is that the chosen -mtune option is
not recorded in the .config.
Another downside is that if there's ever a need to do more complicated
logic to calculate the correct option, that gets messy in the Makefile.
So move the determination of which -mtune option to use into Kconfig
logic.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230329234308.2215833-1-mpe@ellerman.id.au
lppaca_shared_proc() takes a pointer to the lppaca which is typically
accessed through get_lppaca(). With DEBUG_PREEMPT enabled, this leads
to checking if preemption is enabled, for example:
BUG: using smp_processor_id() in preemptible [00000000] code: grep/10693
caller is lparcfg_data+0x408/0x19a0
CPU: 4 PID: 10693 Comm: grep Not tainted 6.5.0-rc3 #2
Call Trace:
dump_stack_lvl+0x154/0x200 (unreliable)
check_preemption_disabled+0x214/0x220
lparcfg_data+0x408/0x19a0
...
This isn't actually a problem however, as it does not matter which
lppaca is accessed, the shared proc state will be the same.
vcpudispatch_stats_procfs_init() already works around this by disabling
preemption, but the lparcfg code does not, erroring any time
/proc/powerpc/lparcfg is accessed with DEBUG_PREEMPT enabled.
Instead of disabling preemption on the caller side, rework
lppaca_shared_proc() to not take a pointer and instead directly access
the lppaca, bypassing any potential preemption checks.
Fixes: f13c13a005 ("powerpc: Stop using non-architected shared_proc field in lppaca")
Signed-off-by: Russell Currey <ruscur@russell.cc>
[mpe: Rework to avoid needing a definition in paca.h and lppaca.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230823055317.751786-4-mpe@ellerman.id.au
The only callers of zalloc_maybe_bootmem() are PCI setup routines. These
used to be called early during boot before slab setup, and also during
runtime due to hotplug.
But commit 5537fcb319 ("powerpc/pci: Add ppc_md.discover_phbs()")
moved the boot-time calls later, after slab setup, meaning there's no
longer any need for zalloc_maybe_bootmem(), kzalloc() can be used in all
cases.
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230823055430.752550-1-mpe@ellerman.id.au
As reported by Mahesh & Aneesh, opal_prd_msg_notifier() triggers a
FORTIFY_SOURCE warning:
memcpy: detected field-spanning write (size 32) of single field "&item->msg" at arch/powerpc/platforms/powernv/opal-prd.c:355 (size 4)
WARNING: CPU: 9 PID: 660 at arch/powerpc/platforms/powernv/opal-prd.c:355 opal_prd_msg_notifier+0x174/0x188 [opal_prd]
NIP opal_prd_msg_notifier+0x174/0x188 [opal_prd]
LR opal_prd_msg_notifier+0x170/0x188 [opal_prd]
Call Trace:
opal_prd_msg_notifier+0x170/0x188 [opal_prd] (unreliable)
notifier_call_chain+0xc0/0x1b0
atomic_notifier_call_chain+0x2c/0x40
opal_message_notify+0xf4/0x2c0
This happens because the copy is targeting item->msg, which is only 4
bytes in size, even though the enclosing item was allocated with extra
space following the msg.
To fix the warning define struct opal_prd_msg with a union of the header
and a flex array, and have the memcpy target the flex array.
Reported-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Reported-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Tested-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230821142820.497107-1-mpe@ellerman.id.au
As of commit b7fb14d3ac ("ide: remove the legacy ide driver") in
v5.14, there are no more generic users of <asm/ide.h>.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Radix vmemmap mapping can map things correctly at the PMD level or PTE
level based on different device boundary checks. Hence we skip the
restrictions w.r.t vmemmap size to be multiple of PMD_SIZE. This also
makes the feature widely useful because to use PMD_SIZE vmemmap area we
require a memory block size of 2GiB
We can also use MHP_RESERVE_PAGES_MEMMAP_ON_MEMORY to that the feature can
work with a memory block size of 256MB. Using altmap.reserve feature to
align things correctly at pageblock granularity. We can end up losing
some pages in memory with this. For ex: with a 256MiB memory block size,
we require 4 pages to map vmemmap pages, In order to align things
correctly we end up adding a reserve of 28 pages. ie, for every 4096
pages 28 pages get reserved.
Link: https://lkml.kernel.org/r/20230808091501.287660-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implicit vma locking inside vm_flags_reset() and vm_flags_reset_once() is
not obvious and makes it hard to understand where vma locking is happening.
Also in some cases (like in dup_userfaultfd()) vma should be locked earlier
than vma_flags modification. To make locking more visible, change these
functions to assert that the vma write lock is taken and explicitly lock
the vma beforehand. Fix userfaultfd functions which should lock the vma
earlier.
Link: https://lkml.kernel.org/r/20230804152724.3090321-5-surenb@google.com
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
walk_page_range() and friends often operate under write-locked mmap_lock.
With introduction of vma locks, the vmas have to be locked as well during
such walks to prevent concurrent page faults in these areas. Add an
additional member to mm_walk_ops to indicate locking requirements for the
walk.
The change ensures that page walks which prevent concurrent page faults
by write-locking mmap_lock, operate correctly after introduction of
per-vma locks. With per-vma locks page faults can be handled under vma
lock without taking mmap_lock at all, so write locking mmap_lock would
not stop them. The change ensures vmas are properly locked during such
walks.
A sample issue this solves is do_mbind() performing queue_pages_range()
to queue pages for migration. Without this change a concurrent page
can be faulted into the area and be left out of migration.
Link: https://lkml.kernel.org/r/20230804152724.3090321-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Suggested-by: Jann Horn <jannh@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
GCC v13.1 updated support for -fpatchable-function-entry on ppc64le to
emit nops after the local entry point, rather than before it. This
allows us to use this in the kernel for ftrace purposes. A new script is
added under arch/powerpc/tools/ to help detect if nops are emitted after
the function local entry point, or before the global entry point.
With -fpatchable-function-entry, we no longer have the profiling
instructions generated at function entry, so we only need to validate
the presence of two nops at the ftrace location in ftrace_init_nop(). We
patch the preceding instruction with 'mflr r0' to match the
-mprofile-kernel ABI for subsequent ftrace use.
This changes the profiling instructions used on ppc32. The default -pg
option emits an additional 'stw' instruction after 'mflr r0' and before
the branch to _mcount 'bl _mcount'. This is very similar to the original
-mprofile-kernel implementation on ppc64le, where an additional 'std'
instruction was used to save LR to its save location in the caller's
stackframe. Subsequently, this additional store was removed in later
compiler versions for performance reasons. The same reasons apply for
ppc32 so we only patch in a 'mflr r0'.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/68586d22981a2c3bb45f27a2b621173d10a7d092.1687166935.git.naveen@kernel.org
Implement ftrace_replace_code() to consolidate logic from the different
ftrace patching routines: ftrace_make_nop(), ftrace_make_call() and
ftrace_modify_call(). Note that ftrace_make_call() is still required
primarily to handle patching modules during their load time. The other
two routines should no longer be called.
This lays the groundwork to enable better control in patching ftrace
locations, including the ability to nop-out preceding profiling
instructions when ftrace is disabled.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/c28f852225646b0561bbf3c1d22d03f041ace8e0.1687166935.git.naveen@kernel.org
Now that we validate the ftrace location during initialization in
ftrace_init_nop(), we can simplify ftrace_modify_call() to patch-in the
updated branch instruction without worrying about the instructions
surrounding the ftrace location. Note that we continue to ensure we
have the expected branch instruction at the ftrace location before
patching it with the updated branch destination.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/06275720939f8ee4c2f61c9e9a3e89b1fa3c441d.1687166935.git.naveen@kernel.org
Commit 67361cf807 ("powerpc/ftrace: Handle large kernel configs")
added ftrace support for ppc64 kernel images with a text section larger
than 32MB. The patch did two things:
1. Add stubs at the end of .text to branch into ftrace_[regs_]caller for
functions that were out of branch range.
2. Re-purpose linker-generated long branches to _mcount to instead branch
to ftrace_[regs_]caller.
Before that, we only supported kernel .text up to ~32MB. With the above,
we now support up to ~96MB:
- The first 32MB of kernel text can branch directly into
ftrace_[regs_]caller since that symbol is usually at the beginning.
- The modified long_branch from (2) above is used by the next 32MB of
kernel text.
- The next 32MB of kernel text can use the stub at the end of text to
branch back to ftrace_[regs_]caller.
While re-purposing the long branch works in practice, it still restricts
ftrace to kernel text up to ~96MB. The stub at the end of kernel text
from (1) already enables us to extend ftrace support for kernel text
up to 64MB, which fulfils the original requirement. Further, once we
switch to -fpatchable-function-entry, there will not be a long branch
that we can use.
Stop re-purposing the linker-generated long branches for ftrace to
simplify the code. If there are good reasons to support ftrace on
kernels beyond 64MB, we can consider adding support by using
-fpatchable-function-entry.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/33fa3be97f8e1f2171254ef2e1b0d5c8836c11fd.1687166935.git.naveen@kernel.org
ftrace_low.S has just the _mcount stub and return_to_handler(). Merge
this back into ftrace_mprofile.S and ftrace_64_pg.S to keep all ftrace
code together, and to allow those to evolve independently.
ftrace_mprofile.S is also not an entirely accurate name since this also
holds ppc32 code. This will be all the more incorrect once support for
-fpatchable-function-entry is added. Rename files here to more
accurately describe the code:
- ftrace_mprofile.S is renamed to ftrace_entry.S
- ftrace_pg.c is renamed to ftrace_64_pg.c
- ftrace_64_pg.S is rename to ftrace_64_pg_entry.S
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/b900c9a8bba9d6c3c295e0f99886acf3e5bf6f7b.1687166935.git.naveen@kernel.org
Commit 67361cf807 ("powerpc/ftrace: Handle large kernel configs")
added ftrace support for ppc64 kernel images with a text section larger
than 32MB. The approach itself isn't specific to ppc64, so extend the
same to also work on ppc32.
While at it, reduce the space reserved for the stub from 64 bytes to 32
bytes since the different stub variants are all less than 8
instructions.
To reduce use of #ifdef, a stub implementation is provided for
kernel_toc_address() and -SZ_2G is cast to 'long long' to prevent
errors on ppc32.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/9fa3258cbb9105cf8a0a8135214d44ffbc75fe84.1687166935.git.naveen@kernel.org
ELFv1 support is deprecated and on the way out. Pre -mprofile-kernel
ftrace support (-pg only) is very limited and is retained primarily for
clang builds. It won't be necessary once clang lands support for
-fpatchable-function-entry.
Copy the existing ftrace code supporting these into ftrace_pg.c.
ftrace.c can then be refactored and enhanced with a focus on ppc32 and
ppc64 ELFv2.
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/1eb6cc6c3141ddb77a2a25f8a9e83d83ff312b02.1687166935.git.naveen@kernel.org
The minimum level of gcc supported for building the kernel is v5.1.
v5.x releases of gcc emitted a three instruction sequence for
-mprofile-kernel:
mflr r0
std r0, 16(r1)
bl _mcount
It is only with the v6.x releases that gcc started emitting the two
instruction sequence for -mprofile-kernel, omitting the second store
instruction.
With the older three instruction sequence, the actual ftrace location
can be the 5th instruction into a function. Update the allowed offset
for ftrace location from 12 to 16 to accommodate the same.
Cc: stable@vger.kernel.org
Fixes: 7af82ff90a ("powerpc/ftrace: Ignore weak functions")
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/7b265908a9461e38fc756ef9b569703860a80621.1687166935.git.naveen@kernel.org
Pull powerpc fix from Michael Ellerman:
- Fix hardened usercopy BUG when using /proc based firmware update
interface
Thanks to Nathan Lynch and Kees Cook.
* tag 'powerpc-6.5-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/rtas_flash: allow user copy to flash block cache objects
The APIs that allow backtracing across CPUs have always had a way to
exclude the current CPU. This convenience means callers didn't need to
find a place to allocate a CPU mask just to handle the common case.
Let's extend the API to take a CPU ID to exclude instead of just a
boolean. This isn't any more complex for the API to handle and allows the
hardlockup detector to exclude a different CPU (the one it already did a
trace for) without needing to find space for a CPU mask.
Arguably, this new API also encourages safer behavior. Specifically if
the caller wants to avoid tracing the current CPU (maybe because they
already traced the current CPU) this makes it more obvious to the caller
that they need to make sure that the current CPU ID can't change.
[akpm@linux-foundation.org: fix trigger_allbutcpu_cpu_backtrace() stub]
Link: https://lkml.kernel.org/r/20230804065935.v4.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
