Commit Graph

582 Commits

Author SHA1 Message Date
Christophe Leroy de40303b54 powerpc/ppc-opcode: Define and use PPC_RAW_SETB()
We have PPC_INST_SETB then build the 'setb' instruction in the
user.

Instead, define PPC_RAW_SETB() and use it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b08a4f26919a8f8cdcf7544ab552d9c1c63418b5.1657205708.git.christophe.leroy@csgroup.eu
2022-07-27 21:36:05 +10:00
Michael Ellerman 2a83afe72a powerpc/64: Drop ppc_inst_as_str()
The ppc_inst_as_str() macro tries to make printing variable length,
aka "prefixed", instructions convenient. It mostly succeeds, but it does
hide an on-stack buffer, which triggers stack protector.

More problematically it doesn't compile at all with GCC 12,
with -Wdangling-pointer, due to the fact that it returns the char buffer
declared inside the macro:

  arch/powerpc/kernel/trace/ftrace.c: In function '__ftrace_modify_call':
  ./include/linux/printk.h:475:44: error: using a dangling pointer to '__str' [-Werror=dangling-pointer=]
    475 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
    ...
  arch/powerpc/kernel/trace/ftrace.c:567:17: note: in expansion of macro 'pr_err'
    567 |                 pr_err("Not expected bl: opcode is %s\n", ppc_inst_as_str(op));
        |                 ^~~~~~
  ./arch/powerpc/include/asm/inst.h:156:14: note: '__str' declared here
    156 |         char __str[PPC_INST_STR_LEN];   \
        |              ^~~~~

This could be fixed by having the caller declare the buffer, but in some
places there'd need to be two buffers. In all cases where
ppc_inst_as_str() is used the output is not really meant for user
consumption, it's almost always indicative of a kernel bug.

A simpler solution is to just print the value as an unsigned long. For
normal instructions the output is identical. For prefixed instructions
the value is printed as a single 64-bit quantity, whereas previously the
low half was printed first. But that is good enough for debug output,
especially as prefixed instructions will be rare in kernel code in
practice.

Old:
  c000000000111170  60420000      ori     r2,r2,0
  c000000000111174  04100001 e580fb00     .long 0xe580fb0004100001

New:
  c00000000010f90c  60420000      ori     r2,r2,0
  c00000000010f910  e580fb0004100001      .long 0xe580fb0004100001

Reported-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reported-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20220531065936.3674348-1-mpe@ellerman.id.au
2022-06-29 19:37:07 +10:00
Linus Torvalds 6112bd00e8 powerpc updates for 5.19
- Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT).
 
  - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later).
 
  - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ.
 
  - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later.
 
  - Drop support for system call instruction emulation.
 
  - Many other small features and fixes.
 
 Thanks to: Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas Sanjaya, Bjorn
 Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian King, Daniel Axtens, Dwaipayan
 Ray, Fabiano Rosas, Finn Thain, Frank Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu
 Hua, Haowen Bai, Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing
 Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof Kozlowski, Laurent
 Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes, Miaoqian Lin, Minghao Chi, Nathan
 Chancellor, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár,
 Paul Mackerras, Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib
 Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang wangx, Xiaomeng Tong,
 Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing, Yu Kuai, Zheng Bin, Zou Wei, Zucheng
 Zheng.
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Merge tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)

 - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later)

 - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ

 - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later

 - Drop support for system call instruction emulation

 - Many other small features and fixes

Thanks to Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas
Sanjaya, Bjorn Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian
King, Daniel Axtens, Dwaipayan Ray, Fabiano Rosas, Finn Thain, Frank
Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu Hua, Haowen Bai,
Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing
Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof
Kozlowski, Laurent Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes,
Miaoqian Lin, Minghao Chi, Nathan Chancellor, Naveen N. Rao, Nicholas
Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár, Paul Mackerras,
Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib
Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang
wangx, Xiaomeng Tong, Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing,
Yu Kuai, Zheng Bin, Zou Wei, and Zucheng Zheng.

* tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits)
  powerpc/64: Include cache.h directly in paca.h
  powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU is set
  powerpc/xics: Include missing header
  powerpc/powernv/pci: Drop VF MPS fixup
  powerpc/fsl_book3e: Don't set rodata RO too early
  powerpc/microwatt: Add mmu bits to device tree
  powerpc/powernv/flash: Check OPAL flash calls exist before using
  powerpc/powermac: constify device_node in of_irq_parse_oldworld()
  powerpc/powermac: add missing g5_phy_disable_cpu1() declaration
  selftests/powerpc/pmu: fix spelling mistake "mis-match" -> "mismatch"
  powerpc: Enable the DAWR on POWER9 DD2.3 and above
  powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask
  powerpc/64s: Add CPU_FTRS_POWER9_DD2_2 to CPU_FTRS_ALWAYS mask
  powerpc: Fix all occurences of "the the"
  selftests/powerpc/pmu/ebb: remove fixed_instruction.S
  powerpc/platforms/83xx: Use of_device_get_match_data()
  powerpc/eeh: Drop redundant spinlock initialization
  powerpc/iommu: Add missing of_node_put in iommu_init_early_dart
  powerpc/pseries/vas: Call misc_deregister if sysfs init fails
  powerpc/papr_scm: Fix leaking nvdimm_events_map elements
  ...
2022-05-28 11:27:17 -07:00
Daniel Axtens 5352090a99 powerpc/kasan: Don't instrument non-maskable or raw interrupts
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
2022-05-22 15:58:29 +10:00
Christophe Leroy 4390a58ee1 powerpc/inst: Remove PPC_INST_BRANCH
Convert last users of PPC_INST_BRANCH to PPC_RAW_BRANCH()

And remove PPC_INST_BRANCH.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fa8807108a2ef2287a2c9651d6e1ff7c051923d9.1652074503.git.christophe.leroy@csgroup.eu
2022-05-22 15:58:27 +10:00
Christophe Leroy bbffdd2fc7 powerpc/ftrace: Use patch_instruction() return directly
Instead of returning -EPERM when patch_instruction() fails,
just return what patch_instruction returns.

That simplifies ftrace_modify_code():

	   0:	94 21 ff c0 	stwu    r1,-64(r1)
	   4:	93 e1 00 3c 	stw     r31,60(r1)
	   8:	7c 7f 1b 79 	mr.     r31,r3
	   c:	40 80 00 30 	bge     3c <ftrace_modify_code+0x3c>
	  10:	93 c1 00 38 	stw     r30,56(r1)
	  14:	7c 9e 23 78 	mr      r30,r4
	  18:	7c a4 2b 78 	mr      r4,r5
	  1c:	80 bf 00 00 	lwz     r5,0(r31)
	  20:	7c 1e 28 40 	cmplw   r30,r5
	  24:	40 82 00 34 	bne     58 <ftrace_modify_code+0x58>
	  28:	83 c1 00 38 	lwz     r30,56(r1)
	  2c:	7f e3 fb 78 	mr      r3,r31
	  30:	83 e1 00 3c 	lwz     r31,60(r1)
	  34:	38 21 00 40 	addi    r1,r1,64
	  38:	48 00 00 00 	b       38 <ftrace_modify_code+0x38>
				38: R_PPC_REL24	patch_instruction

Before:

	   0:	94 21 ff c0 	stwu    r1,-64(r1)
	   4:	93 e1 00 3c 	stw     r31,60(r1)
	   8:	7c 7f 1b 79 	mr.     r31,r3
	   c:	40 80 00 4c 	bge     58 <ftrace_modify_code+0x58>
	  10:	93 c1 00 38 	stw     r30,56(r1)
	  14:	7c 9e 23 78 	mr      r30,r4
	  18:	7c a4 2b 78 	mr      r4,r5
	  1c:	80 bf 00 00 	lwz     r5,0(r31)
	  20:	7c 08 02 a6 	mflr    r0
	  24:	90 01 00 44 	stw     r0,68(r1)
	  28:	7c 1e 28 40 	cmplw   r30,r5
	  2c:	40 82 00 48 	bne     74 <ftrace_modify_code+0x74>
	  30:	7f e3 fb 78 	mr      r3,r31
	  34:	48 00 00 01 	bl      34 <ftrace_modify_code+0x34>
				34: R_PPC_REL24	patch_instruction
	  38:	80 01 00 44 	lwz     r0,68(r1)
	  3c:	20 63 00 00 	subfic  r3,r3,0
	  40:	83 c1 00 38 	lwz     r30,56(r1)
	  44:	7c 63 19 10 	subfe   r3,r3,r3
	  48:	7c 08 03 a6 	mtlr    r0
	  4c:	83 e1 00 3c 	lwz     r31,60(r1)
	  50:	38 21 00 40 	addi    r1,r1,64
	  54:	4e 80 00 20 	blr

It improves ftrace activation/deactivation duration by about 3%.

Modify patch_instruction() return on failure to -EPERM in order to
match with ftrace expectations. Other users of patch_instruction()
do not care about the exact error value returned.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/49a8597230713e2633e7d9d7b56140787c4a7e20.1652074503.git.christophe.leroy@csgroup.eu
2022-05-19 23:11:28 +10:00
Christophe Leroy d2f47dabf1 powerpc/code-patching: Inline create_branch()
create_branch() is a good candidate for inlining because:
- Flags can be folded in.
- Range tests are likely to be already done.

Hence reducing the create_branch() to only a set of instructions.

So inline it.

It improves ftrace activation by 10%.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/69851cc9a7bf8f03d025e6d29e165f2d0bd3bb6e.1652074503.git.christophe.leroy@csgroup.eu
2022-05-19 23:11:28 +10:00
Christophe Leroy 1acbf27e8a powerpc/code-patching: Inline is_offset_in_{cond}_branch_range()
Test in is_offset_in_branch_range() and is_offset_in_cond_branch_range()
are simple tests that are worth inlining.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a05be0ccb7373e6a9789a1988fcd0c810f5f9269.1652074503.git.christophe.leroy@csgroup.eu
2022-05-19 23:11:28 +10:00
Christophe Leroy 1751289268 powerpc/code-patching: Use jump_label to check if poking_init() is done
It's only during early startup that poking_init() is not done yet,
for instance when calling ftrace_init().

Once poking_init() has been called there must be a poking area, no
need to check it everytime patch_instruction() is called.

ftrace activation time is reduced by 7% with the change on an 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8d6088aca7b63247377b6d9e4897d08d935fbe93.1647962456.git.christophe.leroy@csgroup.eu
2022-05-11 23:06:39 +10:00
Christophe Leroy b033767848 powerpc/code-patching: Use jump_label for testing freed initmem
Once init is done, initmem is freed forever so no need to
test system_state at every call to patch_instruction().

Use jump_label.

This reduces by 2% the time needed to activate ftrace on an 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0aee964721cab7316cffde21a2ca223cee14d373.1647962456.git.christophe.leroy@csgroup.eu
2022-05-11 23:06:39 +10:00
Christophe Leroy cb3ac45214 powerpc/code-patching: Don't call is_vmalloc_or_module_addr() without CONFIG_MODULES
If CONFIG_MODULES is not set, there is no point in checking
whether text is in module area.

This reduced the time needed to activate/deactivate ftrace
by more than 10% on an 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f3c701cce00a38620788c0fc43ff0b611a268c54.1647962456.git.christophe.leroy@csgroup.eu
2022-05-08 22:15:41 +10:00
Nicholas Piggin a553476c44 powerpc/64: remove system call instruction emulation
emulate_step() instruction emulation including sc instruction emulation
initially appeared in xmon. It was then moved into sstep.c where kprobes
could use it too, and later hw_breakpoint and uprobes started to use it.

Until uprobes, the only instruction emulation users were for kernel
mode instructions.

- xmon only steps / breaks on kernel addresses.
- kprobes is kernel only.
- hw_breakpoint only emulates kernel instructions, single steps user.

At one point, there was support for the kernel to execute sc
instructions, although that is long removed and it's not clear whether
there were any in-tree users. So system call emulation is not required
by the above users.

uprobes uses emulate_step and it appears possible to emulate sc
instruction in userspace. Userspace system call emulation is broken and
it's not clear it ever worked well.

The big complication is that userspace takes an interrupt to the kernel
to emulate the instruction. The user->kernel interrupt sets up registers
and interrupt stack frame expecting to return to userspace, then system
call instruction emulation re-directs that stack frame to the kernel,
early in the system call interrupt handler. This means the interrupt
return code takes the kernel->kernel restore path, which does not
restore everything as the system call interrupt handler would expect
coming from userspace. regs->iamr appears to get lost for example,
because the kernel->kernel return does not restore the user iamr.
Accounting such as irqflags tracing and CPU accounting does not get
flipped back to user mode as the system call handler expects, so those
appear to enter the kernel twice without returning to userspace.

These things may be individually fixable with various complication, but
it is a big complexity for unclear real benefit.

Furthermore, it is not possible to single step a system call instruction
since it causes an interrupt. As such, a separate patch disables probing
on system call instructions.

This patch removes system call emulation and disables stepping system
calls.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[minor commit log edit, and also get rid of '#ifdef CONFIG_PPC64']
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a412e3b3791ed83de18704c8d90f492e7a0049c0.1648648712.git.naveen.n.rao@linux.vnet.ibm.com
2022-05-06 00:00:20 +10:00
Yang Li 9923a6dace powerpc/sstep: Use bitwise instead of arithmetic operator for flags
Fix the following coccinelle warnings:
./arch/powerpc/lib/sstep.c:1090:20-21: WARNING: sum of probable
bitmasks, consider |
./arch/powerpc/lib/sstep.c:1115:20-21: WARNING: sum of probable
bitmasks, consider |
./arch/powerpc/lib/sstep.c:1134:20-21: WARNING: sum of probable
bitmasks, consider |

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.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/1613811455-2457-1-git-send-email-yang.lee@linux.alibaba.com
2022-05-02 23:02:15 +10:00
Christoph Hellwig 6308499b5e net: unexport csum_and_copy_{from,to}_user
csum_and_copy_from_user and csum_and_copy_to_user are exported by a few
architectures, but not actually used in modular code.  Drop the exports.

Link: https://lkml.kernel.org/r/20220421070440.1282704-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-29 14:37:59 -07:00
Linus Torvalds 1f1c153e40 powerpc updates for 5.18
- Enforce kernel RO, and implement STRICT_MODULE_RWX for 603.
 
  - Add support for livepatch to 32-bit.
 
  - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS.
 
  - Merge vdso64 and vdso32 into a single directory.
 
  - Fix build errors with newer binutils.
 
  - Add support for UADDR64 relocations, which are emitted by some toolchains. This allows
    powerpc to build with the latest lld.
 
  - Fix (another) potential userspace r13 corruption in transactional memory handling.
 
  - Cleanups of function descriptor handling & related fixes to LKDTM.
 
 Thanks to: Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh Kumar K.V, Anton
 Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar Chowdhury, Cédric Le Goater, Chen
 Jingwen, Christophe JAILLET, Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel
 Henrique Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu Hua, Haren
 Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason Wang, Jeremy Kerr, Joachim
 Wiberg, Jordan Niethe, Julia Lawall, Kajol Jain, Kees Cook, Laurent Dufour, Madhavan
 Srinivasan, Mamatha Inamdar, Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal
 Suchanek, Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nour-eddine
 Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy Dunlap, Ritesh Harjani, Rohan
 McLure, Russell Currey, Sachin Sant, Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain,
 Thierry Reding, Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean, Wedson
 Almeida Filho, YueHaibing.
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Merge tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Livepatch support for 32-bit is probably the standout new feature,
  otherwise mostly just lots of bits and pieces all over the board.

  There's a series of commits cleaning up function descriptor handling,
  which touches a few other arches as well as LKDTM. It has acks from
  Arnd, Kees and Helge.

  Summary:

   - Enforce kernel RO, and implement STRICT_MODULE_RWX for 603.

   - Add support for livepatch to 32-bit.

   - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS.

   - Merge vdso64 and vdso32 into a single directory.

   - Fix build errors with newer binutils.

   - Add support for UADDR64 relocations, which are emitted by some
     toolchains. This allows powerpc to build with the latest lld.

   - Fix (another) potential userspace r13 corruption in transactional
     memory handling.

   - Cleanups of function descriptor handling & related fixes to LKDTM.

  Thanks to Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh
  Kumar K.V, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar
  Chowdhury, Cédric Le Goater, Chen Jingwen, Christophe JAILLET,
  Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel Henrique
  Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu
  Hua, Haren Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason
  Wang, Jeremy Kerr, Joachim Wiberg, Jordan Niethe, Julia Lawall, Kajol
  Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mamatha Inamdar,
  Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal Suchanek,
  Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
  Nour-eddine Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy
  Dunlap, Ritesh Harjani, Rohan McLure, Russell Currey, Sachin Sant,
  Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain, Thierry Reding,
  Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean,
  Wedson Almeida Filho, and YueHaibing"

* tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc/pseries: Fix use after free in remove_phb_dynamic()
  powerpc/time: improve decrementer clockevent processing
  powerpc/time: Fix KVM host re-arming a timer beyond decrementer range
  powerpc/tm: Fix more userspace r13 corruption
  powerpc/xive: fix return value of __setup handler
  powerpc/64: Add UADDR64 relocation support
  powerpc: 8xx: fix a return value error in mpc8xx_pic_init
  powerpc/ps3: remove unneeded semicolons
  powerpc/64: Force inlining of prevent_user_access() and set_kuap()
  powerpc/bitops: Force inlining of fls()
  powerpc: declare unmodified attribute_group usages const
  powerpc/spufs: Fix build warning when CONFIG_PROC_FS=n
  powerpc/secvar: fix refcount leak in format_show()
  powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E
  powerpc: Move C prototypes out of asm-prototypes.h
  powerpc/kexec: Declare kexec_paca static
  powerpc/smp: Declare current_set static
  powerpc: Cleanup asm-prototypes.c
  powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S
  powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S
  ...
2022-03-25 09:39:36 -07:00
Linus Torvalds 194dfe88d6 asm-generic updates for 5.18
There are three sets of updates for 5.18 in the asm-generic tree:
 
  - The set_fs()/get_fs() infrastructure gets removed for good. This
    was already gone from all major architectures, but now we can
    finally remove it everywhere, which loses some particularly
    tricky and error-prone code.
    There is a small merge conflict against a parisc cleanup, the
    solution is to use their new version.
 
  - The nds32 architecture ends its tenure in the Linux kernel. The
    hardware is still used and the code is in reasonable shape, but
    the mainline port is not actively maintained any more, as all
    remaining users are thought to run vendor kernels that would never
    be updated to a future release.
    There are some obvious conflicts against changes to the removed
    files.
 
  - A series from Masahiro Yamada cleans up some of the uapi header
    files to pass the compile-time checks.
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Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "There are three sets of updates for 5.18 in the asm-generic tree:

   - The set_fs()/get_fs() infrastructure gets removed for good.

     This was already gone from all major architectures, but now we can
     finally remove it everywhere, which loses some particularly tricky
     and error-prone code. There is a small merge conflict against a
     parisc cleanup, the solution is to use their new version.

   - The nds32 architecture ends its tenure in the Linux kernel.

     The hardware is still used and the code is in reasonable shape, but
     the mainline port is not actively maintained any more, as all
     remaining users are thought to run vendor kernels that would never
     be updated to a future release.

   - A series from Masahiro Yamada cleans up some of the uapi header
     files to pass the compile-time checks"

* tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits)
  nds32: Remove the architecture
  uaccess: remove CONFIG_SET_FS
  ia64: remove CONFIG_SET_FS support
  sh: remove CONFIG_SET_FS support
  sparc64: remove CONFIG_SET_FS support
  lib/test_lockup: fix kernel pointer check for separate address spaces
  uaccess: generalize access_ok()
  uaccess: fix type mismatch warnings from access_ok()
  arm64: simplify access_ok()
  m68k: fix access_ok for coldfire
  MIPS: use simpler access_ok()
  MIPS: Handle address errors for accesses above CPU max virtual user address
  uaccess: add generic __{get,put}_kernel_nofault
  nios2: drop access_ok() check from __put_user()
  x86: use more conventional access_ok() definition
  x86: remove __range_not_ok()
  sparc64: add __{get,put}_kernel_nofault()
  nds32: fix access_ok() checks in get/put_user
  uaccess: fix nios2 and microblaze get_user_8()
  sparc64: fix building assembly files
  ...
2022-03-23 18:03:08 -07:00
Linus Torvalds 93e220a62d Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - hwrng core now credits for low-quality RNG devices.

  Algorithms:
   - Optimisations for neon aes on arm/arm64.
   - Add accelerated crc32_be on arm64.
   - Add ffdheXYZ(dh) templates.
   - Disallow hmac keys < 112 bits in FIPS mode.
   - Add AVX assembly implementation for sm3 on x86.

  Drivers:
   - Add missing local_bh_disable calls for crypto_engine callback.
   - Ensure BH is disabled in crypto_engine callback path.
   - Fix zero length DMA mappings in ccree.
   - Add synchronization between mailbox accesses in octeontx2.
   - Add Xilinx SHA3 driver.
   - Add support for the TDES IP available on sama7g5 SoC in atmel"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (137 commits)
  crypto: xilinx - Turn SHA into a tristate and allow COMPILE_TEST
  MAINTAINERS: update HPRE/SEC2/TRNG driver maintainers list
  crypto: dh - Remove the unused function dh_safe_prime_dh_alg()
  hwrng: nomadik - Change clk_disable to clk_disable_unprepare
  crypto: arm64 - cleanup comments
  crypto: qat - fix initialization of pfvf rts_map_msg structures
  crypto: qat - fix initialization of pfvf cap_msg structures
  crypto: qat - remove unneeded assignment
  crypto: qat - disable registration of algorithms
  crypto: hisilicon/qm - fix memset during queues clearing
  crypto: xilinx: prevent probing on non-xilinx hardware
  crypto: marvell/octeontx - Use swap() instead of open coding it
  crypto: ccree - Fix use after free in cc_cipher_exit()
  crypto: ccp - ccp_dmaengine_unregister release dma channels
  crypto: octeontx2 - fix missing unlock
  hwrng: cavium - fix NULL but dereferenced coccicheck error
  crypto: cavium/nitrox - don't cast parameter in bit operations
  crypto: vmx - add missing dependencies
  MAINTAINERS: Add maintainer for Xilinx ZynqMP SHA3 driver
  crypto: xilinx - Add Xilinx SHA3 driver
  ...
2022-03-21 16:02:36 -07:00
Christophe Leroy 76222808fc powerpc: Move C prototypes out of asm-prototypes.h
We originally added asm-prototypes.h in commit 42f5b4cacd ("powerpc:
Introduce asm-prototypes.h"). It's purpose was for prototypes of C
functions that are only called from asm, in order to fix sparse
warnings about missing prototypes.

A few months later Nick added a different use case in
commit 4efca4ed05 ("kbuild: modversions for EXPORT_SYMBOL() for asm")
for C prototypes for exported asm functions. This is basically the
inverse of our original usage.

Since then we've added various prototypes to asm-prototypes.h for both
reasons, meaning we now need to unstitch it all.

Dispatch prototypes of C functions into relevant headers and keep
only the prototypes for functions defined in assembly.

For the time being, leave prom_init() there because moving it
into asm/prom.h or asm/setup.h conflicts with
drivers/gpu/drm/nouveau/nvkm/subdev/bios/shadowrom.o
This will be fixed later by untaggling asm/pci.h and asm/prom.h
or by renaming the function in shadowrom.c

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/62d46904eca74042097acf4cb12c175e3067f3d1.1646413435.git.christophe.leroy@csgroup.eu
2022-03-08 22:06:25 +11:00
Michael Ellerman 591b4b2684 powerpc/code-patching: Pre-map patch area
Paul reported a warning with DEBUG_ATOMIC_SLEEP=y:

  BUG: sleeping function called from invalid context at include/linux/sched/mm.h:256
  in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
  preempt_count: 0, expected: 0
  ...
  Call Trace:
    dump_stack_lvl+0xa0/0xec (unreliable)
    __might_resched+0x2f4/0x310
    kmem_cache_alloc+0x220/0x4b0
    __pud_alloc+0x74/0x1d0
    hash__map_kernel_page+0x2cc/0x390
    do_patch_instruction+0x134/0x4a0
    arch_jump_label_transform+0x64/0x78
    __jump_label_update+0x148/0x180
    static_key_enable_cpuslocked+0xd0/0x120
    static_key_enable+0x30/0x50
    check_kvm_guest+0x60/0x88
    pSeries_smp_probe+0x54/0xb0
    smp_prepare_cpus+0x3e0/0x430
    kernel_init_freeable+0x20c/0x43c
    kernel_init+0x30/0x1a0
    ret_from_kernel_thread+0x5c/0x64

Peter pointed out that this is because do_patch_instruction() has
disabled interrupts, but then map_patch_area() calls map_kernel_page()
then hash__map_kernel_page() which does a sleeping memory allocation.

We only see the warning in KVM guests with SMT enabled, which is not
particularly common, or on other platforms if CONFIG_KPROBES is
disabled, also not common. The reason we don't see it in most
configurations is that another path that happens to have interrupts
enabled has allocated the required page tables for us, eg. there's a
path in kprobes init that does that. That's just pure luck though.

As Christophe suggested, the simplest solution is to do a dummy
map/unmap when we initialise the patching, so that any required page
table levels are pre-allocated before the first call to
do_patch_instruction(). This works because the unmap doesn't free any
page tables that were allocated by the map, it just clears the PTE,
leaving the page table levels there for the next map.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Debugged-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220223015821.473097-1-mpe@ellerman.id.au
2022-03-08 00:04:57 +11:00
Anders Roxell 8219d31eff powerpc/lib/sstep: Fix build errors with newer binutils
Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian
2.37.90.20220207) the following build error shows up:

  {standard input}: Assembler messages:
  {standard input}:10576: Error: unrecognized opcode: `stbcx.'
  {standard input}:10680: Error: unrecognized opcode: `lharx'
  {standard input}:10694: Error: unrecognized opcode: `lbarx'

Rework to add assembler directives [1] around the instruction.  The
problem with this might be that we can trick a power6 into
single-stepping through an stbcx. for instance, and it will execute that
in kernel mode.

[1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo

Fixes: 350779a29f ("powerpc: Handle most loads and stores in instruction emulation code")
Cc: stable@vger.kernel.org # v4.14+
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220224162215.3406642-3-anders.roxell@linaro.org
2022-03-01 23:51:09 +11:00
Anders Roxell a633cb1edd powerpc/lib/sstep: Fix 'sthcx' instruction
Looks like there been a copy paste mistake when added the instruction
'stbcx' twice and one was probably meant to be 'sthcx'. Changing to
'sthcx' from 'stbcx'.

Fixes: 350779a29f ("powerpc: Handle most loads and stores in instruction emulation code")
Cc: stable@vger.kernel.org # v4.14+
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220224162215.3406642-1-anders.roxell@linaro.org
2022-03-01 23:51:08 +11:00
Arnd Bergmann 23fc539e81 uaccess: fix type mismatch warnings from access_ok()
On some architectures, access_ok() does not do any argument type
checking, so replacing the definition with a generic one causes
a few warnings for harmless issues that were never caught before.

Fix the ones that I found either through my own test builds or
that were reported by the 0-day bot.

Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-25 09:36:05 +01:00
Anders Roxell fe663df782 powerpc/lib/sstep: fix 'ptesync' build error
Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian
2.37.90.20220207) the following build error shows up:

  {standard input}: Assembler messages:
  {standard input}:2088: Error: unrecognized opcode: `ptesync'
  make[3]: *** [/builds/linux/scripts/Makefile.build:287: arch/powerpc/lib/sstep.o] Error 1

Add the 'ifdef CONFIG_PPC64' around the 'ptesync' in function
'emulate_update_regs()' to like it is in 'analyse_instr()'. Since it looks like
it got dropped inadvertently by commit 3cdfcbfd32 ("powerpc: Change
analyse_instr so it doesn't modify *regs").

A key detail is that analyse_instr() will never recognise lwsync or
ptesync on 32-bit (because of the existing ifdef), and as a result
emulate_update_regs() should never be called with an op specifying
either of those on 32-bit. So removing them from emulate_update_regs()
should be a nop in terms of runtime behaviour.

Fixes: 3cdfcbfd32 ("powerpc: Change analyse_instr so it doesn't modify *regs")
Cc: stable@vger.kernel.org # v4.14+
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
[mpe: Add last paragraph of change log mentioning analyse_instr() details]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220211005113.1361436-1-anders.roxell@linaro.org
2022-02-15 22:31:35 +11:00
Christophe Leroy 6836f09903 powerpc/lib/sstep: use truncate_if_32bit()
Use truncate_if_32bit() when possible instead of open coding.

truncate_if_32bit() returns an unsigned long, so don't use it when
a signed value is expected.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7e1c07123f13156d4a27991a2e2694fb584bc068.1642752375.git.christophe.leroy@csgroup.eu
2022-02-12 22:47:43 +11:00
Christophe Leroy 7c3bba9199 powerpc/lib/sstep: Remove unneeded #ifdef __powerpc64__
MSR_64BIT is always defined, no need to hide code using MSR_64BIT
inside an #ifdef __powerpc64__

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ee61b693bc7e046eed1abb7a34909eb4878a9442.1642752375.git.christophe.leroy@csgroup.eu
2022-02-12 22:47:43 +11:00
Christophe Leroy 67484e0de9 powerpc/lib/sstep: Use l1_dcache_bytes() instead of opencoding
Don't opencode dcache size retrieval based on whether that's ppc32 or ppc64.

Use l1_dcache_bytes()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6c608fd4795e2d8ea1a0a449405a0087f76d8bb3.1642752375.git.christophe.leroy@csgroup.eu
2022-02-12 22:47:42 +11:00
Ard Biesheuvel 297565aa22 lib/xor: make xor prototypes more friendly to compiler vectorization
Modern compilers are perfectly capable of extracting parallelism from
the XOR routines, provided that the prototypes reflect the nature of the
input accurately, in particular, the fact that the input vectors are
expected not to overlap. This is not documented explicitly, but is
implied by the interchangeability of the various C routines, some of
which use temporary variables while others don't: this means that these
routines only behave identically for non-overlapping inputs.

So let's decorate these input vectors with the __restrict modifier,
which informs the compiler that there is no overlap. While at it, make
the input-only vectors pointer-to-const as well.

Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/563
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-02-11 20:39:39 +11:00
Christophe Leroy 1231816373 powerpc/32: Remove remaining .stabs annotations
STABS debug format has been superseded long time ago by DWARF.

Remove the few remaining .stabs annotations from old 32 bits code.

Reported-by: kernel test robot <lkp@intel.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/68932ec2ba6b868d35006b96e90f0890f3da3c05.1638273868.git.christophe.leroy@csgroup.eu
2022-02-07 21:03:10 +11:00
Christophe Leroy bba496656a powerpc/32: Fix boot failure with GCC latent entropy plugin
Boot fails with GCC latent entropy plugin enabled.

This is due to early boot functions trying to access 'latent_entropy'
global data while the kernel is not relocated at its final
destination yet.

As there is no way to tell GCC to use PTRRELOC() to access it,
disable latent entropy plugin in early_32.o and feature-fixups.o and
code-patching.o

Fixes: 38addce8b6 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217
Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.1640178426.git.christophe.leroy@csgroup.eu
2021-12-23 22:36:58 +11:00
Christophe Leroy 309a0a6018 powerpc/code-patching: Replace patch_instruction() by ppc_inst_write() in selftests
The purpose of selftests is to check that instructions are
properly formed. Not to check that they properly run.

For that test it uses normal memory, not special test
memory.

In preparation of a future patch enforcing patch_instruction()
to be used only on valid text areas, implement a ppc_inst_write()
instruction which is the complement of ppc_inst_read(). This
new function writes the formated instruction in valid kernel
memory and doesn't bother about icache.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7cf5335cc07ca9b6f8cdaa20ca9887fce4df3bea.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:36:58 +11:00
Christophe Leroy f30a578d76 powerpc/code-patching: Move code patching selftests in its own file
Code patching selftests are half of code-patching.c.
As they are guarded by CONFIG_CODE_PATCHING_SELFTESTS,
they'd be better in their own file.

Also add a missing __init for instr_is_branch_to_addr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c0c30504f04eb546a48ff77127a8bccd12a3d809.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:36:58 +11:00
Christophe Leroy 31acc59956 powerpc/code-patching: Move instr_is_branch_{i/b}form() in code-patching.h
To enable moving selftests in their own C file in following patch,
move instr_is_branch_iform() and instr_is_branch_bform()
to code-patching.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fca0f3b191211b3681020885a611bf73eef20563.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:36:58 +11:00
Christophe Leroy 29562a9da2 powerpc/code-patching: Move patch_exception() outside code-patching.c
patch_exception() is dedicated to book3e/64 is nothing more than
a normal use of patch_branch(), so move it into a place dedicated
to book3e/64.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0968622b98b1fb51838c35b844c42ad6609de62e.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:36:55 +11:00
Christophe Leroy ff14a9c09f powerpc/code-patching: Use test_trampoline for prefixed patch test
Use the dedicated test_trampoline function for testing prefixed
patching like other tests and remove the hand coded assembly stuff.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a450ef3f8653f75e1bd9aaf7a3889d379752f33b.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:25 +11:00
Christophe Leroy d5937db114 powerpc/code-patching: Fix patch_branch() return on out-of-range failure
Do not silentely ignore a failure of create_branch() in
patch_branch(). Return -ERANGE.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8540cb64b1f06710eaf41e3835c7ba3e21fa2b05.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Christophe Leroy 6b21af7449 powerpc/code-patching: Reorganise do_patch_instruction() to ease error handling
Split do_patch_instruction() in two functions, the caller doing the
spin locking and the callee doing everything else.

And remove a few unnecessary initialisations and intermediate
variables.

This allows the callee to return from anywhere in the function.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/dbc85980a0d2a935731b272e8907e8bb1d8fc8c5.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Christophe Leroy a3483c3dd1 powerpc/code-patching: Fix unmap_patch_area() error handling
pXd_offset() doesn't return NULL. When the base is NULL, it
still adds the offset.

Use pXd_none() to check validity instead. It also improves
performance by folding out none existing levels as pXd_none()
always returns 0 in that case.

Such an error is unexpected, use WARN_ON() so that the caller
doesn't have to worry about it, and drop the returned value.

And now that unmap_patch_area() doesn't return error, we can
take into account the error returned by __patch_instruction().

While at it, remove the 'inline' property which is useless.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/299804b117fae35c786c827536c91f25352e279b.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Christophe Leroy 285672f993 powerpc/code-patching: Fix error handling in do_patch_instruction()
Use real errors instead of using -1 as error, so that errors
returned by callees can be used towards callers.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/85259d894069e47f915ea580b169e1adbeec7a61.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Christophe Leroy af5304a750 powerpc/code-patching: Remove init_mem_is_free
A new state has been added by commit d2635f2012 ("mm: create a new
system state and fix core_kernel_text()"). That state tells when
initmem is about to be released and is redundant with init_mem_is_free.

Remove init_mem_is_free.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ad8c3ccb39c8edaa89fd3eda1cc7218baea1cde5.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Christophe Leroy edecd2d6d6 powerpc/code-patching: Remove pr_debug()/pr_devel() messages and fix check()
code-patching has been working for years now, time has come to
remove debugging messages.

Change useful message to KERN_INFO and remove other ones.

Also add KERN_ERR to check() macro and change it into a do/while
to make checkpatch happy.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3ff9823c0a812a8a145d979a9600a6d4591b80ee.1638446239.git.christophe.leroy@csgroup.eu
2021-12-23 22:35:24 +11:00
Nick Child ce0c6be9c6 powerpc/lib: Add __init attribute to eligible functions
Some functions defined in 'arch/powerpc/lib' are deserving of an `__init`
macro attribute. These functions are only called by other initialization
functions and therefore should inherit the attribute.
Also, change function declarations in header files to include `__init`.

Signed-off-by: Nick Child <nick.child@ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211216220035.605465-3-nick.child@ibm.com
2021-12-23 22:33:10 +11:00
Christophe Leroy c545b9f040 powerpc/inst: Define ppc_inst_t
In order to stop using 'struct ppc_inst' on PPC32,
define a ppc_inst_t typedef.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fe5baa2c66fea9db05a8b300b3e8d2880a42596c.1638208156.git.christophe.leroy@csgroup.eu
2021-12-09 22:41:21 +11:00
Nicholas Piggin aebd1fb45c powerpc: flexible GPR range save/restore macros
Introduce macros that operate on a (start, end) range of GPRs, which
reduces lines of code and need to do mental arithmetic while reading the
code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211022061322.2671178-1-npiggin@gmail.com
2021-11-29 23:15:20 +11:00
Michael Ellerman af3fdce4ab Revert "powerpc/code-patching: Improve verification of patchability"
This reverts commit 8b8a8f0ab3.

As reported[1] by Sachin this causes problems with ftrace, and it also
causes the code patching selftests to fail as reported[2] by Stephen.

So revert it for now.

1: https://lore.kernel.org/linuxppc-dev/3668743C-09DF-4673-B15C-2FFE2A57F7D7@linux.vnet.ibm.com/
2: https://lore.kernel.org/linuxppc-dev/20211126161747.1f7795b0@canb.auug.org.au/

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2021-11-29 17:41:52 +11:00
Christophe Leroy 8b8a8f0ab3 powerpc/code-patching: Improve verification of patchability
Today, patch_instruction() assumes that it is called exclusively on
valid addresses, and only checks that it is not called on an init
address after init section has been freed.

Improve verification by calling kernel_text_address() instead.

kernel_text_address() already includes a verification of
initmem release.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bc683d499a411730504b132a924de0ccc2ef1f79.1636971137.git.christophe.leroy@csgroup.eu
2021-11-25 11:25:32 +11:00
Linus Torvalds 1e9ed9360f Kbuild updates for v5.16
- Remove the global -isystem compiler flag, which was made possible by
    the introduction of <linux/stdarg.h>
 
  - Improve the Kconfig help to print the location in the top menu level
 
  - Fix "FORCE prerequisite is missing" build warning for sparc
 
  - Add new build targets, tarzst-pkg and perf-tarzst-src-pkg, which generate
    a zstd-compressed tarball
 
  - Prevent gen_init_cpio tool from generating a corrupted cpio when
    KBUILD_BUILD_TIMESTAMP is set to 2106-02-07 or later
 
  - Misc cleanups
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Merge tag 'kbuild-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Remove the global -isystem compiler flag, which was made possible by
   the introduction of <linux/stdarg.h>

 - Improve the Kconfig help to print the location in the top menu level

 - Fix "FORCE prerequisite is missing" build warning for sparc

 - Add new build targets, tarzst-pkg and perf-tarzst-src-pkg, which
   generate a zstd-compressed tarball

 - Prevent gen_init_cpio tool from generating a corrupted cpio when
   KBUILD_BUILD_TIMESTAMP is set to 2106-02-07 or later

 - Misc cleanups

* tag 'kbuild-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits)
  kbuild: use more subdir- for visiting subdirectories while cleaning
  sh: remove meaningless archclean line
  initramfs: Check timestamp to prevent broken cpio archive
  kbuild: split DEBUG_CFLAGS out to scripts/Makefile.debug
  gen_init_cpio: add static const qualifiers
  kbuild: Add make tarzst-pkg build option
  scripts: update the comments of kallsyms support
  sparc: Add missing "FORCE" target when using if_changed
  kconfig: refactor conf_touch_dep()
  kconfig: refactor conf_write_dep()
  kconfig: refactor conf_write_autoconf()
  kconfig: add conf_get_autoheader_name()
  kconfig: move sym_escape_string_value() to confdata.c
  kconfig: refactor listnewconfig code
  kconfig: refactor conf_write_symbol()
  kconfig: refactor conf_write_heading()
  kconfig: remove 'const' from the return type of sym_escape_string_value()
  kconfig: rename a variable in the lexer to a clearer name
  kconfig: narrow the scope of variables in the lexer
  kconfig: Create links to main menu items in search
  ...
2021-11-08 09:15:45 -08:00
Linus Torvalds 5c0b0c676a powerpc updates for 5.16
- Enable STRICT_KERNEL_RWX for Freescale 85xx platforms.
 
  - Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it to be disabled.
 
  - Add support for out-of-line static calls on 32-bit.
 
  - Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled.
 
  - Fix boot hangs on e5500 due to stale value in ESR passed to do_page_fault().
 
  - Fix several bugs on pseries in handling of device tree cache information for hotplugged
    CPUs, and/or during partition migration.
 
  - Various other small features and fixes.
 
 Thanks to: Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin, Andrew Donnellan,
 Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le Goater, Christophe Leroy, Daniel
 Axtens, Daniel Henrique Barboza, Denis Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo
 A. R. Silva, Hari Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent
 Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Naveen N.
 Rao, Nicholas Piggin, Nick Desaulniers, Niklas Schnelle, Oliver O'Halloran, Rob Herring,
 Russell Currey, Srikar Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant
 Hegde, Wan Jiabing, Xiaoming Ni,
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Merge tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Enable STRICT_KERNEL_RWX for Freescale 85xx platforms.

 - Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it
   to be disabled.

 - Add support for out-of-line static calls on 32-bit.

 - Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled.

 - Fix boot hangs on e5500 due to stale value in ESR passed to
   do_page_fault().

 - Fix several bugs on pseries in handling of device tree cache
   information for hotplugged CPUs, and/or during partition migration.

 - Various other small features and fixes.

Thanks to Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin,
Andrew Donnellan, Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le
Goater, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Denis
Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo A.  R.  Silva, Hari
Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent
Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan
Lynch, Naveen N.  Rao, Nicholas Piggin, Nick Desaulniers, Niklas
Schnelle, Oliver O'Halloran, Rob Herring, Russell Currey, Srikar
Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant
Hegde, Wan Jiabing, and Xiaoming Ni,

* tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (73 commits)
  powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST
  powerpc/32e: Ignore ESR in instruction storage interrupt handler
  powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload
  powerpc: Don't provide __kernel_map_pages() without ARCH_SUPPORTS_DEBUG_PAGEALLOC
  MAINTAINERS: Update powerpc KVM entry
  powerpc/xmon: fix task state output
  powerpc/44x/fsp2: add missing of_node_put
  powerpc/dcr: Use cmplwi instead of 3-argument cmpli
  KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling
  powerpc/security: Use a mutex for interrupt exit code patching
  powerpc/83xx/mpc8349emitx: Make mcu_gpiochip_remove() return void
  powerpc/fsl_booke: Fix setting of exec flag when setting TLBCAMs
  powerpc/book3e: Fix set_memory_x() and set_memory_nx()
  powerpc/nohash: Fix __ptep_set_access_flags() and ptep_set_wrprotect()
  powerpc/bpf: Fix write protecting JIT code
  selftests/powerpc: Use date instead of EPOCHSECONDS in mitigation-patching.sh
  powerpc/64s/interrupt: Fix check_return_regs_valid() false positive
  powerpc/boot: Set LC_ALL=C in wrapper script
  powerpc/64s: Default to 64K pages for 64 bit book3s
  Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC"
  ...
2021-11-05 08:15:46 -07:00
Russell Currey 3c12b4df8d powerpc/security: Use a mutex for interrupt exit code patching
The mitigation-patching.sh script in the powerpc selftests toggles
all mitigations on and off simultaneously, revealing that rfi_flush
and stf_barrier cannot safely operate at the same time due to races
in updating the static key.

On some systems, the static key code throws a warning and the kernel
remains functional.  On others, the kernel will hang or crash.

Fix this by slapping on a mutex.

Fixes: 13799748b9 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Russell Currey <ruscur@russell.cc>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211027072410.40950-1-ruscur@russell.cc
2021-10-28 17:23:58 +11:00
Christophe Leroy e28d0b6750 powerpc/lib/sstep: Don't use __{get/put}_user() on kernel addresses
In the old days, when we didn't have kernel userspace access
protection and had set_fs(), it was wise to use __get_user()
and friends to read kernel memory.

Nowadays, get_user() and put_user() are granting userspace access and
are exclusively for userspace access.

Convert single step emulation functions to user_access_begin() and
friends and use unsafe_get_user() and unsafe_put_user().

When addressing kernel addresses, there is no need to open userspace
access. And for book3s/32 it is particularly important to no try and
open userspace access on kernel address, because that would break the
content of kernel space segment registers. No guard has been put
against that risk in order to avoid degrading performance.

copy_from_kernel_nofault() and copy_to_kernel_nofault() should
be used but they are out-of-line functions which would degrade
performance. Those two functions are making use of
__get_kernel_nofault() and __put_kernel_nofault() macros.
Those two macros are just wrappers behind __get_user_size_goto() and
__put_user_size_goto().

unsafe_get_user() and unsafe_put_user() are also wrappers of
__get_user_size_goto() and __put_user_size_goto(). Use them to
access kernel space. That allows refactoring userspace and
kernelspace access.

Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Depends-on: 4fe5cda9f8 ("powerpc/uaccess: Implement user_read_access_begin and user_write_access_begin")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/22831c9d17f948680a12c5292e7627288b15f713.1631817805.git.christophe.leroy@csgroup.eu
2021-10-22 15:22:05 +11:00
Naveen N. Rao 4549c3ea31 powerpc/lib: Add helper to check if offset is within conditional branch range
Add a helper to check if a given offset is within the branch range for a
powerpc conditional branch instruction, and update some sites to use the
new helper.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/442b69a34ced32ca346a0d9a855f3f6cfdbbbd41.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
2021-10-07 18:52:33 +11:00