powerpc/io: Remove PPC_IO_WORKAROUNDS

The Cell blade support was the last user of PPC_IO_WORKAROUNDS, so they
can now be removed.

Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by:

powerpc/io: Remove PPC_IO_WORKAROUNDS

The Cell blade support was the last user of PPC_IO_WORKAROUNDS, so they
can now be removed.

Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Madhavan Srinivasan <[email protected]>
Link: https://patch.msgid.link/[email protected]

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powerpc: Remove PPC_OF_PLATFORM_PCI

The Cell blade support was the last user of PPC_OF_PLATFORM_PCI, so
remove it.

Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Madhavan Srini

powerpc: Remove PPC_OF_PLATFORM_PCI

The Cell blade support was the last user of PPC_OF_PLATFORM_PCI, so
remove it.

Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Madhavan Srinivasan <[email protected]>
Link: https://patch.msgid.link/[email protected]

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powerpc: Replace kretprobe code with rethook on powerpc

This is an adaptation of commit f3a112c0c40d ("x86,rethook,kprobes:
Replace kretprobe with rethook on x86") to powerpc.

Rethook follows the e

powerpc: Replace kretprobe code with rethook on powerpc

This is an adaptation of commit f3a112c0c40d ("x86,rethook,kprobes:
Replace kretprobe with rethook on x86") to powerpc.

Rethook follows the existing kretprobe implementation, but separates
it from kprobes so that it can be used by fprobe (ftrace-based
function entry/exit probes). As such, this patch also enables fprobe
to work on powerpc. The only other change compared to the existing
kretprobe implementation is doing the return address fixup in
arch_rethook_fixup_return().

Reference to other archs:
commit b57c2f124098 ("riscv: add riscv rethook implementation")
commit 7b0a096436c2 ("LoongArch: Replace kretprobe with rethook")

Note:
=====

In future, rethook will be only for kretprobe, and kretprobe
will be replaced by fprobe.

https://lore.kernel.org/all/172000134410.63468.13742222887213469474.stgit@devnote2/

We will adapt the above implementation for powerpc once its upstream.
Until then, we can have this implementation of rethook to serve
current kretprobe usecases.

Reviewed-by: Naveen Rao <[email protected]>
Signed-off-by: Abhishek Dubey <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc: Remove core support for 40x

Now that 40x platforms have gone, remove support
for 40x in the core of powerpc arch.

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-b

powerpc: Remove core support for 40x

Now that 40x platforms have gone, remove support
for 40x in the core of powerpc arch.

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large

All supported compilers today (gcc v5.1+ and clang v11+) have support for
-mcmodel=medium. As such, NO_MINIMAL_TOC is no l

powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large

All supported compilers today (gcc v5.1+ and clang v11+) have support for
-mcmodel=medium. As such, NO_MINIMAL_TOC is no longer being set. Remove
NO_MINIMAL_TOC as well as the fallback to -mminimal-toc.

Reviewed-by: Christophe Leroy <[email protected]>
Signed-off-by: Naveen N Rao <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc: remove unused *_syscall_64.o variables in Makefile

Commit ab1a517d55b0 ("powerpc/syscall: Rename syscall_64.c into
interrupt.c") missed to update these three lines:

GCOV_PROFILE_syscall_

powerpc: remove unused *_syscall_64.o variables in Makefile

Commit ab1a517d55b0 ("powerpc/syscall: Rename syscall_64.c into
interrupt.c") missed to update these three lines:

GCOV_PROFILE_syscall_64.o := n
KCOV_INSTRUMENT_syscall_64.o := n
UBSAN_SANITIZE_syscall_64.o := n

To restore the original behavior, we could replace them with:

GCOV_PROFILE_interrupt.o := n
KCOV_INSTRUMENT_interrupt.o := n
UBSAN_SANITIZE_interrupt.o := n

However, nobody has noticed the functional change in the past three
years, so they were unneeded.

Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/dexcr: Reset DEXCR value across exec

Inheriting the DEXCR across exec can have security and usability
concerns. If a program is compiled with hash instructions it generally
expects to run wi

powerpc/dexcr: Reset DEXCR value across exec

Inheriting the DEXCR across exec can have security and usability
concerns. If a program is compiled with hash instructions it generally
expects to run with NPHIE enabled. But if the parent process disables
NPHIE then if it's not careful it will be disabled for any children too
and the protection offered by hash checks is basically worthless.

This patch introduces a per-process reset value that new execs in a
particular process tree are initialized with. This enables fine grained
control over what DEXCR value child processes run with by default.
For example, containers running legacy binaries that expect hash
instructions to act as NOPs could configure the reset value of the
container root to control the default reset value for all members of
the container.

Signed-off-by: Benjamin Gray <[email protected]>
[mpe: Add missing SPDX tag on dexcr.c]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc: remove unused KCSAN_SANITIZE_early_64.o in Makefile

Commit 2fb857bc9f9e ("powerpc/kcsan: Add exclusions from instrumentation")
added KCSAN_SANITIZE_early_64.o to arch/powerpc/kernel/Makefil

powerpc: remove unused KCSAN_SANITIZE_early_64.o in Makefile

Commit 2fb857bc9f9e ("powerpc/kcsan: Add exclusions from instrumentation")
added KCSAN_SANITIZE_early_64.o to arch/powerpc/kernel/Makefile, while
it does not compile early_64.o.

Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/64: Rename entry_64.S to prom_entry_64.S

This file contains only the enter_prom implementation now.
Trim includes and update header comment while we're here.

Signed-off-by: Nicholas Piggin

powerpc/64: Rename entry_64.S to prom_entry_64.S

This file contains only the enter_prom implementation now.
Trim includes and update header comment while we're here.

Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc: merge 32-bit and 64-bit _switch implementation

The _switch stack frame setup are substantially the same, so are the
comments. The difference in how the stack and current are switched,
and o

powerpc: merge 32-bit and 64-bit _switch implementation

The _switch stack frame setup are substantially the same, so are the
comments. The difference in how the stack and current are switched,
and other hardware and software housekeeping is done is moved into
macros.

Generated code should be unchanged.

Signed-off-by: Nicholas Piggin <[email protected]>
[mpe: Tweak include orer to fix compile errors on some configs]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/kcsan: Add exclusions from instrumentation

Exclude various incompatible compilation units from KCSAN
instrumentation.

Signed-off-by: Rohan McLure <[email protected]>
Signed-off-by: Mich

powerpc/kcsan: Add exclusions from instrumentation

Exclude various incompatible compilation units from KCSAN
instrumentation.

Signed-off-by: Rohan McLure <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc/32: fix syscall wrappers with 64-bit arguments of unaligned register-pairs

powerpc 32-bit system call (and function) calling convention for 64-bit
arguments requires the next available odd-p

powerpc/32: fix syscall wrappers with 64-bit arguments of unaligned register-pairs

powerpc 32-bit system call (and function) calling convention for 64-bit
arguments requires the next available odd-pair (two sequential registers
with the first being odd-numbered) from the standard register argument
allocation.

The first argument register is r3, so a 64-bit argument that appears at
an even position in the argument list must skip a register (unless there
were preceding 64-bit arguments, which might throw things off). This
requires non-standard compat definitions to deal with the holes in the
argument register allocation.

With pt_regs syscall wrappers which use a standard mapper to map pt_regs
GPRs to function arguments, 32-bit kernels hit the same basic problem,
the standard definitions don't cope with the unused argument registers.

Fix this by having 32-bit kernels share those syscall definitions with
compat.

Thanks to Jason for spending a lot of time finding and bisecting this
and developing a trivial reproducer. The perfect bug report.

Reported-by: Jason A. Donenfeld <[email protected]>
Signed-off-by: Nicholas Piggin <[email protected]>
Fixes: 7e92e01b72452 ("powerpc: Provide syscall wrapper")
Reviewed-by: Arnd Bergmann <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc: Fix 85xx build

The merge of the kbuild tree dropped the renaming of the FSL_BOOKE
kconfig option.

Fixes: 8afc66e8d43b ("Merge tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel

powerpc: Fix 85xx build

The merge of the kbuild tree dropped the renaming of the FSL_BOOKE
kconfig option.

Fixes: 8afc66e8d43b ("Merge tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild")
Signed-off-by: Joel Stanley <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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kbuild: use obj-y instead extra-y for objects placed at the head

The objects placed at the head of vmlinux need special treatments:

- arch/$(SRCARCH)/Makefile adds them to head-y in order to place

kbuild: use obj-y instead extra-y for objects placed at the head

The objects placed at the head of vmlinux need special treatments:

- arch/$(SRCARCH)/Makefile adds them to head-y in order to place
them before other archives in the linker command line.

- arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of
obj-y to avoid them going into built-in.a.

This commit gets rid of the latter.

Create vmlinux.a to collect all the objects that are unconditionally
linked to vmlinux. The objects listed in head-y are moved to the head
of vmlinux.a by using 'ar m'.

With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y
for builtin objects.

There is no *.o that is directly linked to vmlinux. Drop unneeded code
in scripts/clang-tools/gen_compile_commands.py.

$(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested
by Nathan Chancellor [1].

[1]: https://lore.kernel.org/llvm/[email protected]/

Signed-off-by: Masahiro Yamada <[email protected]>
Tested-by: Nick Desaulniers <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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powerpc: Cleanup idle for e500

e500 idle setup is a bit messy.

e500_idle() is used for PPC32 while book3e_idle() is used for PPC64.
As they are mutually exclusive, call them all e500_idle().

Use C

powerpc: Cleanup idle for e500

e500 idle setup is a bit messy.

e500_idle() is used for PPC32 while book3e_idle() is used for PPC64.
As they are mutually exclusive, call them all e500_idle().

Use CONFIG_MPC_85xx instead of PPC32 + E500 in Makefile and rename
idle_e500.c to idle_85xx.c .

Rename idle_book3e.c to idle_64e.c and remove #ifdef PPC64 in
as it's only built on PPC64.

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/8039301334e948974c85ec5ef2db37751075185b.1663606876.git.christophe.leroy@csgroup.eu

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powerpc: Remove CONFIG_PPC_FSL_BOOK3E

CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500.

Remove it.

And rename five files accordingly.

Signed-off-by: Christophe Leroy <christophe.leroy@csgr

powerpc: Remove CONFIG_PPC_FSL_BOOK3E

CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500.

Remove it.

And rename five files accordingly.

Signed-off-by: Christophe Leroy <[email protected]>
[mpe: Rename include guards to match new file names]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/795cb93b88c9a0279289712e674f39e3b108a1b4.1663606876.git.christophe.leroy@csgroup.eu

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powerpc: Change CONFIG_E500 to CONFIG_PPC_E500

It will be used outside arch/powerpc, make it clear its a
powerpc configuration item.

And we already have CONFIG_PPC_E500MC, so that will make
it more

powerpc: Change CONFIG_E500 to CONFIG_PPC_E500

It will be used outside arch/powerpc, make it clear its a
powerpc configuration item.

And we already have CONFIG_PPC_E500MC, so that will make
it more consistent.

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/e63b22083c11c4300f4a82d3123a46e5fdd54fa6.1663606876.git.christophe.leroy@csgroup.eu

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powerpc: Remove CONFIG_FSL_BOOKE

PPC_85xx is PPC32 only.
PPC_85xx always selects E500 and is the only PPC32 that
selects E500.
FSL_BOOKE is selected when E500 and PPC32 are selected.

So FSL_BOOKE i

powerpc: Remove CONFIG_FSL_BOOKE

PPC_85xx is PPC32 only.
PPC_85xx always selects E500 and is the only PPC32 that
selects E500.
FSL_BOOKE is selected when E500 and PPC32 are selected.

So FSL_BOOKE is redundant with PPC_85xx.

Remove FSL_BOOKE.

And rename four files accordingly.

cpu_setup_fsl_booke.S is not renamed because it is linked to
PPC_FSL_BOOK3E and not to FSL_BOOKE as suggested by its name.

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/08e3e15594e66d63b9e89c5b4f9c35153913c28f.1663606875.git.christophe.leroy@csgroup.eu

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powerpc: add support for syscall stack randomization

Add support for adding a random offset to the stack while handling
syscalls. This patch uses mftb() instead of get_random_int() for better
perfor

powerpc: add support for syscall stack randomization

Add support for adding a random offset to the stack while handling
syscalls. This patch uses mftb() instead of get_random_int() for better
performance.

In order to avoid unconditional stack canaries on syscall entry (due to
the use of alloca()), also disable stack protector to avoid triggering
needless checks and slowing down the entry path. As there is no general
way to control stack protector coverage with a function attribute, this
must be disabled at the compilation unit level.

Signed-off-by: Xiu Jianfeng <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc: Move system_call_exception() to syscall.c

This is a lead-up patch to enable syscall stack randomization, which
uses alloca() and makes the compiler add unconditional stack canaries
on sysca

powerpc: Move system_call_exception() to syscall.c

This is a lead-up patch to enable syscall stack randomization, which
uses alloca() and makes the compiler add unconditional stack canaries
on syscall entry. In order to avoid triggering needless checks and
slowing down the entry path, the feature needs to disable stack
protector at the compilation unit level as there is no general way to
control stack protector coverage with a function attribute.

So move system_call_exception() to syscall.c to avoid affecting other
functions in interrupt.c.

Suggested-by: Michael Ellerman <[email protected]>
Signed-off-by: Xiu Jianfeng <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc/64s: Disable stack variable initialisation for prom_init

With GCC 12 allmodconfig prom_init fails to build:

Error: External symbol 'memset' referenced from prom_init.c
make[2]: *** [arc

powerpc/64s: Disable stack variable initialisation for prom_init

With GCC 12 allmodconfig prom_init fails to build:

Error: External symbol 'memset' referenced from prom_init.c
make[2]: *** [arch/powerpc/kernel/Makefile:204: arch/powerpc/kernel/prom_init_check] Error 1

The allmodconfig build enables KASAN, so all calls to memset in
prom_init should be converted to __memset by the #ifdefs in
asm/string.h, because prom_init must use the non-KASAN instrumented
versions.

The build failure happens because there's a call to memset that hasn't
been caught by the pre-processor and converted to __memset. Typically
that's because it's a memset generated by the compiler itself, and that
is the case here.

With GCC 12, allmodconfig enables CONFIG_INIT_STACK_ALL_PATTERN, which
causes the compiler to emit memset calls to initialise on-stack
variables with a pattern.

Because prom_init is non-user-facing boot-time only code, as a
workaround just disable stack variable initialisation to unbreak the
build.

Reported-by: Sudip Mukherjee <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc/irq: Split irq.c

More than half of irq.c is dedicated to PPC64.

Move PPC64 code out of irq.c into irq_64.c

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Mich

powerpc/irq: Split irq.c

More than half of irq.c is dedicated to PPC64.

Move PPC64 code out of irq.c into irq_64.c

Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/9f1a47de80f78d3dd270a7a72f69f55f581c4054.1652859593.git.christophe.leroy@csgroup.eu

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powerpc/kasan: Mark more real-mode code as not to be instrumented

This marks more files and functions that can possibly be called in
real mode as not to be instrumented by KASAN. Most were found by

powerpc/kasan: Mark more real-mode code as not to be instrumented

This marks more files and functions that can possibly be called in
real mode as not to be instrumented by KASAN. Most were found by
inspection, except for get_pseries_errorlog() which was reported as
causing a crash in testing.

Reported-by: Nageswara R Sastry <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/YoX1kZPnmUX4RZEK@cleo

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powerpc: Book3S 64-bit outline-only KASAN support

Implement a limited form of KASAN for Book3S 64-bit machines running under
the Radix MMU, supporting only outline mode.

- Enable the compiler inst

powerpc: Book3S 64-bit outline-only KASAN support

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.

[[email protected] - 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 <[email protected]> # ppc64 out-of-line radix version
Signed-off-by: Daniel Axtens <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>
[mpe: Update copyright year and comment formatting]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/YoTE69OQwiG7z+Gu@cleo

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powerpc/rtas: Move rtas entry assembly into its own file

This makes working on the code a bit easier.

Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <mpe@ellerma

powerpc/rtas: Move rtas entry assembly into its own file

This makes working on the code a bit easier.

Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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