Back in 2009 we merged 501cb16d "Randomise PIEs", which added support for
randomizing PIE (Position Independent Executable) binaries.

That commit added randomize_et_dyn(), which correctly randomized the addresses,
but failed to honor PF_RANDOMIZE. That means it was not possible to disable PIE
randomization via the personality flag, or /proc/sys/kernel/randomize_va_space.

Since then there has been generic support for PIE randomization added to
binfmt_elf.c, selectable via ARCH_BINFMT_ELF_RANDOMIZE_PIE.

Enabling that allows us to drop randomize_et_dyn(), which means we start
honoring PF_RANDOMIZE correctly.

It also causes a fairly major change to how we layout PIE binaries.

Currently we will place the binary at 512MB-520MB for 32 bit binaries, or
512MB-1.5GB for 64 bit binaries, eg:

    $ cat /proc/$$/maps
    4e550000-4e580000 r-xp 00000000 08:02 129813       /bin/dash
    4e580000-4e590000 rw-p 00020000 08:02 129813       /bin/dash
    10014110000-10014140000 rw-p 00000000 00:00 0      [heap]
    3fffaa3f0000-3fffaa5a0000 r-xp 00000000 08:02 921  /lib/powerpc64le-linux-gnu/libc-2.19.so
    3fffaa5a0000-3fffaa5b0000 rw-p 001a0000 08:02 921  /lib/powerpc64le-linux-gnu/libc-2.19.so
    3fffaa5c0000-3fffaa5d0000 rw-p 00000000 00:00 0
    3fffaa5d0000-3fffaa5f0000 r-xp 00000000 00:00 0    [vdso]
    3fffaa5f0000-3fffaa620000 r-xp 00000000 08:02 1246 /lib/powerpc64le-linux-gnu/ld-2.19.so
    3fffaa620000-3fffaa630000 rw-p 00020000 08:02 1246 /lib/powerpc64le-linux-gnu/ld-2.19.so
    3ffffc340000-3ffffc370000 rw-p 00000000 00:00 0    [stack]

With this commit applied we don't do any special randomisation for the binary,
and instead rely on mmap randomisation. This means the binary ends up at high
addresses, eg:

    $ cat /proc/$$/maps
    3fff99820000-3fff999d0000 r-xp 00000000 08:02 921    /lib/powerpc64le-linux-gnu/libc-2.19.so
    3fff999d0000-3fff999e0000 rw-p 001a0000 08:02 921    /lib/powerpc64le-linux-gnu/libc-2.19.so
    3fff999f0000-3fff99a00000 rw-p 00000000 00:00 0
    3fff99a00000-3fff99a20000 r-xp 00000000 00:00 0      [vdso]
    3fff99a20000-3fff99a50000 r-xp 00000000 08:02 1246   /lib/powerpc64le-linux-gnu/ld-2.19.so
    3fff99a50000-3fff99a60000 rw-p 00020000 08:02 1246   /lib/powerpc64le-linux-gnu/ld-2.19.so
    3fff99a60000-3fff99a90000 r-xp 00000000 08:02 129813 /bin/dash
    3fff99a90000-3fff99aa0000 rw-p 00020000 08:02 129813 /bin/dash
    3fffc3de0000-3fffc3e10000 rw-p 00000000 00:00 0      [stack]
    3fffc55e0000-3fffc5610000 rw-p 00000000 00:00 0      [heap]

Although this should be OK, it's possible it might break badly written
binaries that make assumptions about the address space layout.
Signed-off-by: Vineeth Vijayan <vvijayan@mvista.com>
[mpe: Rewrite changelog]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

If there're no PHBs under P5IOC2 HUB device tree node, we should
bail early to avoid zero devisor and allocating TCE tables.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When freezing compound PEs in pnv_ioda_freeze_pe(), we should bail
upon illegal master PE. We needn't freeze slave PE because it should
have been put into frozen state by hardware.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Nested if statements are always bad and the patch avoids one by
checking PHB type and bail in advance if necessary.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 262af557 ("powerpc/powernv: Enable M64 aperatus for PHB3")
introduced compound PEs in order to support M64 aperatus on PHB3.
However, we never configured PELTV for compound PEs. The patch
fixes that by: parent PE can freeze all child compound PEs. Any
compound PE affects the group.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The patch initializes PE instance when reserving PE number to
keep consistent things as we did before. Also, it replaces the
iteration on bridge's windows with the prefered way.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The patch renames alloc_m64_pe() to reserve_m64_pe() to reflect
its real usage: We reserve PE numbers for M64 segments in advance
and then pick up the reserved PE numbers when building the mapping
between PE numbers and M64 segments.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The M64 resource should be removed if we don't have hook to
initialize it, or (not and) fail to do that.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The patch checks PHB type a bit early to save a bit cycles
for P7 because we don't support M64 for P7IOC no matter what
OPAL firmware we have.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch switch the ppc arch to use the generic RCU based
gup implementation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Update generic gup implementation with powerpc specific details.
On powerpc at pmd level we can have hugepte, normal pmd pointer
or a pointer to the hugepage directory.
Tested-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch add documentation and missing accessors.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Firmware is allowed to communicate to us via the "ibm,pa-features" property
that TM (Transactional Memory) support is disabled.

Currently this doesn't happen on any platform we're aware of, but we should
honor it anyway.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

dump_tlb_44x() is only defined when 44x=y, but the ifdef in xmon.c
checks for 4xx, leading to a build failure:

  arch/powerpc/xmon/xmon.c:912:4: error: implicit declaration of function 'dump_tlb_44x'
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In arch/powerpc/include/asm/bitops.h, the comments about bit numbers in
large (> 1 word) bitmaps have two typos:
- On ppc64 system, the LSB of the 4th word should be bit 192 rather than
  196, because if it's bit 196, bit 192-195 will be missing in the
  bitmap.
- On ppc32 system, the LSB of the second word should be bit 32 rather
  than 31, because bit 31 is already in the first word.

This patch fixes these typos.
Signed-off-by: Boqun Feng <boqun.feng@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Recent OPAL firmare adds a couple of functions to send and receive IPMI
messages:

  https://github.com/open-power/skiboot/commit/b2a374da

This change updates the token list and wrappers to suit, and adds the
platform devices for any IPMI interfaces.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit be96f633 ("powerpc: Split out instruction analysis
part of emulate_step()") added some calls to do_fp_load()
and do_fp_store(), which fail to compile on configs with
CONFIG_PPC_FPU=n and CONFIG_PPC_EMULATE_SSTEP=y.  This fixes
the compile by adding #ifdef CONFIG_PPC_FPU around the code
that calls these functions.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The system call FLIH (first-level interrupt handler) at 0xc00
unconditionally sets hardware priority to medium. For hypercalls, this
means we lose guest OS priority. The front end (do_kvm_0x**) to the
KVM interrupt handler always assumes that PPR priority is saved in
PACA exception save area, so it copies this to the kvm_hstate
structure. For hypercalls, this would be the saved priority from any
previous exception. Eventually, the guest gets resumed with an
incorrect priority.

The fix is to save the PPR priority in PACA exception save area before
switching HMT priorities in the FLIH so that existing code described above
in the KVM interrupt handler can copy it from there into the VCPU's saved
context.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
[mpe: Dropped HMT_MEDIUM_PPR_DISCARD and reworded comment]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

PAGE_FACTOR was defined to reflect the difference between configured
page size and fixed 4KB page size. Replace (PAGE_SHIFT - HW_PAGE_SHIFT)
with PAGE_FACTOR.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We have some code in udbg_uart_getc_poll() that tries to protect
against a NULL udbg_uart_in, but gets it all wrong.

Found with the LLVM static analyzer (scan-build).

Fixes: 30925748 ("powerpc: Cleanup udbg_16550 and add support for LPC PIO-only UARTs")
Signed-off-by: Anton Blanchard <anton@samba.org>
[mpe: Add some newlines for readability while we're here]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Simplify the error path to avoid calling of_node_put when it is not needed.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Of_node_put supports NULL as its argument, so the initial test is not
necessary.

Suggested by Uwe Kleine-König.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

-if (e)
   of_node_put(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Of_node_put supports NULL as its argument, so the initial test is not
necessary.

Suggested by Uwe Kleine-König.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

-if (e)
   of_node_put(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Of_node_put supports NULL as its argument, so the initial test is not
necessary.

Suggested by Uwe Kleine-König.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

-if (e)
   of_node_put(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Simplify the error path to avoid calling of_node_put when it is not needed.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The H_SET_MODE hcall returns H_P2 if a function is not implemented
and all callers should handle this case.

The call to enable relocation on exceptions currently prints an error
message if the feature is not implemented. While H_SET_MODE was
first introduced on POWER8 (which has relocation on exceptions), it
has been now added on some POWER7 configurations (which does not).

Check for H_P2 and print an informational message instead.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The ibm,pcie-link-speed-stats isn't mandatory, so we shouldn't print
a high priority error message when missing. One example where we see
this is QEMU.

Reduce it to pr_debug.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Move the declaration up to silence the warning.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Looks like I introduced this when adding LE support.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

LLVM doesn't support local named register variables and is unlikely
to. current_thread_info is using one, fix it by moving it out and
calling it __current_r1().

I gave it a bit of an obscure name because we don't want anyone else
using it - they should use current_stack_pointer(). This specific
case is performance critical and we can't afford to call a function
to get it. Furthermore it isn't important to know exactly where in
the stack we are since we mask the lower bits.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The build is broken with CONFIG_PPC32=y, CONFIG_FB_VGA16=y and
CONFIG_VGA_CONSOLE=n.

The problem is that vgacon_remap_base is not defined. It's used in:

    #define VGA_MAP_MEM(x,s) (x + vgacon_remap_base)

Which is used in the vga16fb.c code.

Digging down it seems vgacon_remap_base is never initialised. It used to
be, back in arch/ppc (pplus.c and prep_setup.c), but none of that code
ever made it to arch/powerpc.

So given it's been unused for >6 years, remove it.

Whether vga16fb.c works on 32-bit is another question, but this patch
shouldn't affect it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit d4fe0965 ("powerpc/jump_label: use HAVE_JUMP_LABEL?")
missed a few conversions. Change the remaining uses of
CONFIG_JUMP_LABEL to HAVE_JUMP_LABEL.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

On some platforms a 5 second timeout during boot might be quite long, so
make it configurable. Run the loop at least once to let the user stop
the boot by holding a key pressed. If the timeout is set to 0, don't
wait for input, which can be used as a workaround if the boot hangs on
random data coming in on the serial port.
Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
[mpe: Changelog wording & whitespace]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In commit fb5a5157 "Remove platforms/wsp and associated pieces" we
removed the last user of CPU_FTRS_A2, so we should remove it too.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We potentially clear CPU_FTR_HVMODE at runtime in __init_hvmode_206(),
so we must make sure it's not set in CPU_FTRS_ALWAYS.

This doesn't hurt us in practice at the moment, because we don't support
compiling only for CPUs that support CPU_FTR_HVMODE.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

CONFIG_MCOUNT is not defined anymore, the corresponding #ifdef there
is CONFIG_FUNCTION_TRACER.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Added in 2008, but has never had any in-tree users, and no other
architectures provide it.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Instead of passing in the stack address of the link register
to be modified, just pass in the old value and return the
new value and rely on ftrace_graph_caller to do the
modification.

This removes the exception handling around the stack update -
it isn't needed and we weren't consistent about it. Later on
we would do an unprotected modification:

       if (!ftrace_graph_entry(&trace)) {
               *parent = old;
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

mod_return_to_handler is the same as return_to_handler, except
it handles the change of the TOC (r2). Add this into
return_to_handler and remove mod_return_to_handler.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>