linux.git/arch/powerpc/kernel/entry_32.S, branch v4.20

powerpc/traps: merge unrecoverable_exception() and nonrecoverable_exception()

2018-10-03T05:40:01+00:00

PPC32 uses nonrecoverable_exception() while PPC64 uses
unrecoverable_exception().

Both functions are doing almost the same thing.

This patch removes nonrecoverable_exception()

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms

2018-08-07T14:32:24+00:00

Used barrier_nospec to sanitize the syscall table.

Signed-off-by: Diana Craciun 
Signed-off-by: Michael Ellerman

powerpc: clean inclusions of asm/feature-fixups.h

2018-07-30T12:48:17+00:00

files not using feature fixup don't need asm/feature-fixups.h
files using feature fixup need asm/feature-fixups.h

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/405: move PPC405_ERR77 in asm-405.h

2018-07-30T12:48:13+00:00

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc: Add syscall detection for restartable sequences

2018-06-06T09:58:33+00:00

Syscalls are not allowed inside restartable sequences, so add a call to
rseq_syscall() at the very beginning of system call exiting path for
CONFIG_DEBUG_RSEQ=y kernel. This could help us to detect whether there
is a syscall issued inside restartable sequences.

Signed-off-by: Boqun Feng 
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Thomas Gleixner 
Cc: Joel Fernandes 
Cc: Peter Zijlstra 
Cc: Catalin Marinas 
Cc: Dave Watson 
Cc: Will Deacon 
Cc: Andi Kleen 
Cc: Paul Mackerras 
Cc: "H . Peter Anvin" 
Cc: Chris Lameter 
Cc: Russell King 
Cc: Michael Ellerman 
Cc: Andrew Hunter 
Cc: Michael Kerrisk 
Cc: Benjamin Herrenschmidt 
Cc: "Paul E . McKenney" 
Cc: Paul Turner 
Cc: Josh Triplett 
Cc: Steven Rostedt 
Cc: Ben Maurer 
Cc: linux-api@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Andy Lutomirski 
Cc: Andrew Morton 
Cc: Linus Torvalds 
Link: https://lkml.kernel.org/r/20180602124408.8430-10-mathieu.desnoyers@efficios.com

powerpc/8xx: Only perform perf counting when perf is in use.

2018-01-16T12:47:12+00:00

In TLB miss handlers, updating the perf counter is only useful
when performing a perf analysis. As it has a noticeable overhead,
let's only do it when needed.

In order to do so, the exit of the miss handlers will be patched
when starting/stopping 'perf': the first register restore
instruction of each exit point will be replaced by a jump to
the counting code.

Once this is done, CONFIG_PPC_8xx_PERF_EVENT becomes useless as
this feature doesn't add any overhead.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/32: Avoid risk of unrecoverable TLBmiss inside entry_32.S

2017-08-15T12:55:53+00:00

By default, the 8xx pins an ITLB on the first 8M of memory in order
to avoid any ITLB miss on kernel code.
However, with some debug functions like DEBUG_PAGEALLOC and
DEBUG_RODATA, pinning TLBs is contradictory.

In order to avoid any ITLB miss in a critical section without pinning
TLBs, we have to ensure that there is no page boundary crossed between
the setup of a new value in SRR0/SRR1 and the associated RFI.

The functions modifying srr0/srr1 are all located in setup_32.S.
They are spread over almost 4kbytes.

The patch forces a 12 bits (4kbytes) alignment for those
functions. This garanties that the functions remain in a
single 4k page.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/32: Fix boot failure on non 6xx platforms

2017-08-08T09:35:34+00:00

Commit d300627c6a536 ("powerpc/6xx: Handle DABR match before calling
do_page_fault") breaks non 6xx platforms.

  Failed to execute /init (error -14)
  Starting init: /bin/sh exists but couldn't execute it (error -14)
  Kernel panic - not syncing: No working init found.  Try passing init= ...
  CPU: 0 PID: 1 Comm: init Not tainted 4.13.0-rc3-s3k-dev-00143-g7aa62e972a56 #56
  Call Trace:
    panic+0x108/0x250 (unreliable)
    rootfs_mount+0x0/0x58
    ret_from_kernel_thread+0x5c/0x64
  Rebooting in 180 seconds..

This is because in handle_page_fault(), the call to do_page_fault() has been
mistakenly enclosed inside an #ifdef CONFIG_6xx

Fixes: d300627c6a536 ("powerpc/6xx: Handle DABR match before calling do_page_fault")
Brown-paper-bag-to-be-worn-by: Michael Ellerman 
Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

powerpc/6xx: Handle DABR match before calling do_page_fault

2017-08-03T06:06:26+00:00

On legacy 6xx 32-bit procesors, we checked for the DABR match bit
in DSISR from do_page_fault(), in the middle of a pile of ifdef's
because all other CPU types do it in assembly prior to calling
do_page_fault. Fix that.

Signed-off-by: Benjamin Herrenschmidt 
[mpe: Add #ifdef CONFIG_6xx]
Signed-off-by: Michael Ellerman

powerpc: Split ftrace bits into a separate file

2017-04-27T12:20:29+00:00

entry_*.S now includes a lot more than just kernel entry/exit code. As a
first step at cleaning this up, let's split out the ftrace bits into
separate files. Also move all related tracing code into a new trace/
subdirectory.

No functional changes.

Suggested-by: Michael Ellerman 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman