Define the Kconfig symbol so that the kexec_file_load() code can be
built, and wire up the syscall so that it can be called.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This purgatory implementation is based on the versions from kexec-tools
and kexec-lite, with additional changes.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch adds the support code needed for implementing
kexec_file_load() on powerpc.

This consists of functions to load the ELF kernel, either big or little
endian, and setup the purgatory enviroment which switches from the first
kernel to the second kernel.

None of this code is built yet, as it depends on CONFIG_KEXEC_FILE which
we have not yet defined. Although we could define CONFIG_KEXEC_FILE in
this patch, we'd then have a window in history where the kconfig symbol
is present but the syscall is not, which would be awkward.
Signed-off-by: NJosh Sklar <sklar@linux.vnet.ibm.com>
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 2965faa5 ("kexec: split kexec_load syscall from kexec core
code") introduced CONFIG_KEXEC_CORE so that CONFIG_KEXEC means whether
the kexec_load system call should be compiled-in and CONFIG_KEXEC_FILE
means whether the kexec_file_load system call should be compiled-in.
These options can be set independently from each other.

Since until now powerpc only supported kexec_load, CONFIG_KEXEC and
CONFIG_KEXEC_CORE were synonyms. That is not the case anymore, so we
need to make a distinction. Almost all places where CONFIG_KEXEC was
being used should be using CONFIG_KEXEC_CORE instead, since
kexec_file_load also needs that code compiled in.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: NDave Young <dyoung@redhat.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This is done to simplify the kexec_add_buffer argument list.
Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer.

In addition, change the type of kexec_buf.buffer from char * to void *.
There is no particular reason for it to be a char *, and the change
allows us to get rid of 3 existing casts to char * in the code.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: NDave Young <dyoung@redhat.com>
Acked-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.
Signed-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: NDave Young <dyoung@redhat.com>
Acked-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Aneesh/Ben reported that the change to do_page_fault() we made in commit
1d18ad02 ("powerpc/mm: Detect instruction fetch denied and report")
needs to handle the case where CPU_FTR_COHERENT_ICACHE is missing but we
have CPU_FTR_NOEXECUTE. In those cases the check added for
SRR1_ISI_N_OR_G might trigger a false positive.

This patch adds a check for CPU_FTR_COHERENT_ICACHE in addition to the
MSR value.

Fixes: 1d18ad02 ("powerpc/mm: Detect instruction fetch denied and report")
Reported-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that we don't set ARCH incorrectly when calling the boot Makefile,
we can use the generic cpp_lds_S rule for converting our zImage.lds.S
into zImage.lds.

The main advantage of using the generic rule is that it correctly uses
if_changed, which means we correctly regenerate the linker script when
switching endian. Fixing that means we are finally able to build one
endian and then rebuild the other endian without requiring to clean
between builds.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

If we're using if_changed then we must depend on FORCE, so that
if_changed gets a chance to check if something changed.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Back in 2005 when the ppc/ppc64 merge started, we used to build the
kernel code in arch/powerpc but use the boot code from arch/ppc or
arch/ppc64 depending on whether we were building for 32 or 64-bit.

Originally we called the boot Makefile passing ARCH=$(OLDARCH), where
OLDARCH was ppc or ppc64.

In commit 20f62954 ("powerpc: Make building the boot image work for
both 32-bit and 64-bit") (2005-10-11) we split the call for 32/64-bit
using an ifeq check, because the two Makefiles took different targets,
and explicitly passed ARCH=ppc64 for the 64-bit case and ARCH=ppc for
the 32-bit case.

Then in commit 94b212c2 ("powerpc: Move ppc64 boot wrapper code over
to arch/powerpc") (2005-11-16) we moved the boot code into arch/powerpc
and dropped the ppc case, but kept passing ARCH=ppc64 to
arch/powerpc/boot/Makefile.

Since then there have been several more boot targets added, all of which
have copied the ARCH=ppc64 setting, such that now we have four targets
using it.

Currently it seems that nothing actually uses the ARCH value, but that's
basically just luck, and in particular it prevents us from using the
generic cpp_lds_S rule. It's also clearly wrong, ARCH=ppc64 is dead,
buried and cremated.

Fix it by dropping the setting of ARCH completely, the correct value is
exported by the top level Makefile.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This will improve the task exit case, by batching tlb invalidates.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When we are updating a pte, we just need to flush the tlb mapping
that pte. Right now we do a full mm flush because we don't track page
size. Now that we have page size details in pte use that to do the
optimized flush
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

When we are updating a pte, we just need to flush the tlb mapping
that pte. Right now we do a full mm flush because we don't track the page
size. Now that we have page size details in pte use that to do the
optimized flush
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that we have page size details encoded in pte using software pte
bits, use that to find the page size needed for tlb flush.

This function should only be used on P9 DD1, so give it a horrible name
to make that clear.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This patch adds a new software defined pte bit. We use the reserved
fields of ISA 3.0 pte definition since we will only be using this on DD1
code paths. We can possibly look at removing this code later.

The software bit will be used to differentiate between 64K/4K and 2M
ptes. This helps in finding the page size mapping by a pte so that we
can do efficient tlb flush.

We don't support 1G hugetlb pages yet. So we add a DEBUG WARN_ON to
catch wrong usage.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

W.r.t hash page table config, we support 16MB and 16GB as the hugepage
size. Update the hstate_get_psize to handle 16M and 16G.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We will start moving some book3s specific hugetlb functions there.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This converts one that was missed by b1576fec ("powerpc: No need
to use dot symbols when branching to a function").
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

From 80f23935 ("powerpc: Convert cmp to cmpd in idle enter sequence"):

  PowerPC's "cmp" instruction has four operands. Normally people write
  "cmpw" or "cmpd" for the second cmp operand 0 or 1. But, frequently
  people forget, and write "cmp" with just three operands.

  With older binutils this is silently accepted as if this was "cmpw",
  while often "cmpd" is wanted. With newer binutils GAS will complain
  about this for 64-bit code. For 32-bit code it still silently assumes
  "cmpw" is what is meant.

In this case, cmpwi is called for, so this is just a build fix for
new toolchains.

Cc: stable@vger.kernel.org # v3.0+
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

ISA 3 defines new encoded access authority that allows instruction
access prevention in privileged mode and allows normal access
to problem state. This patch just enables IAMR (Instruction Authority
Mask Register), enabling AMR would require more work.

I've tested this with a buggy driver and a simple payload. The payload
is specific to the build I've tested.

mpe: Also tested with LKDTM:

  # echo EXEC_USERSPACE > /sys/kernel/debug/provoke-crash/DIRECT
  lkdtm: Performing direct entry EXEC_USERSPACE
  lkdtm: attempting ok execution at c0000000005bf560
  lkdtm: attempting bad execution at 00003fff8d940000
  Unable to handle kernel paging request for instruction fetch
  Faulting instruction address: 0x3fff8d940000
  Oops: Kernel access of bad area, sig: 11 [#1]
  NIP: 00003fff8d940000 LR: c0000000005bfa58 CTR: 00003fff8d940000
  REGS: c0000000f1fcf900 TRAP: 0400   Not tainted  (4.9.0-rc5-compiler_gcc-6.2.0-00109-g956dbc06232a)
  MSR: 9000000010009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 48002222  XER: 00000000
  ...
  Call Trace:
    lkdtm_EXEC_USERSPACE+0x104/0x120 (unreliable)
    lkdtm_do_action+0x3c/0x80
    direct_entry+0x100/0x1b0
    full_proxy_write+0x94/0x100
    __vfs_write+0x3c/0x1b0
    vfs_write+0xcc/0x230
    SyS_write+0x60/0x110
    system_call+0x38/0xfc
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

ISA 3 allows for prevention of instruction fetch and execution
of user mode pages. If such an error occurs, SRR1 bit 35 reports the
error. We catch and report the error in do_page_fault().
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Setup AMOR (Authority Mask Override Register) in HV mode so that the
host and guest kernel can in turn setup IAMR.

This allows us to enable key 0 in a following patch.
Reported-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NBalbir Singh <bsingharora@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Ensure that PSSCR is set to a safe value corresponding to no
state-loss each time a POWER9 CPU comes online.
Signed-off-by: NGautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-By: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

There is a nice interface for asking ftrace to dump all its tracing
buffers. The only down side for use in xmon is that it uses printk.
Depending on circumstances printk may not work when in xmon, but it also
may, so add a 'dt' command which dumps the ftrace buffers, and add a
note to the help to mentiont that it uses printk.

Calling this routine also disables tracing, which is problematic if you
return from xmon and expect the system to keep operating normally. So
after we do the dump turn tracing back on.

Both functions already have nop versions defined for when ftrace is not
enabled, so we don't need any extra #ifdefs.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Use builtin_platform_driver() helper to simplify the code.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Acked-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Drop duplicate header sched.h from native.c.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In commit d0563a12 ("powerpc: Implement {cmp}xchg for u8 and u16")
we removed the volatile from __cmpxchg().

This is leading to warnings such as:

  drivers/gpu/drm/drm_lock.c: In function ‘drm_lock_take’:
  arch/powerpc/include/asm/cmpxchg.h:484:37: warning: passing argument 1
  of ‘__cmpxchg’ discards ‘volatile’ qualifier from pointer target
     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,   \

There doesn't seem to be consensus across architectures whether the
argument is volatile or not, so at least for now put the volatile back.

Fixes: d0563a12 ("powerpc: Implement {cmp}xchg for u8 and u16")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Merge the topic branch we're sharing with the kvm-ppc tree.

Fix the following coccinelle warnings:

  drivers/misc/cxl/debugfs.c:46:0-23: WARNING: fops_io_x64 should be
      defined with DEFINE_DEBUGFS_ATTRIBUTE
  drivers/misc/cxl/guest.c:890:5-26: WARNING: Comparison to bool
  drivers/misc/cxl/irq.c:107:3-23: WARNING: Assignment of bool to 0/1
  drivers/misc/cxl/native.c:57:2-3: Unneeded semicolon
  drivers/misc/cxl/native.c:170:2-3: Unneeded semicolon
Signed-off-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Partially copied from commit df0698be ("ARM: stack protector:
change the canary value per task")

A new random value for the canary is stored in the task struct whenever
a new task is forked.  This is meant to allow for different canary values
per task.  On powerpc, GCC expects the canary value to be found in a global
variable called __stack_chk_guard.  So this variable has to be updated
with the value stored in the task struct whenever a task switch occurs.

Because the variable GCC expects is global, this cannot work on SMP
unfortunately.  So, on SMP, the same initial canary value is kept
throughout, making this feature a bit less effective although it is still
useful.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Partialy copied from commit c743f380 ("ARM: initial stack protector
(-fstack-protector) support")

This is the very basic stuff without the changing canary upon
task switch yet.  Just the Kconfig option and a constant canary
value initialized at boot time.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Implement xchg{u8,u16}{local,relaxed}, and
cmpxchg{u8,u16}{,local,acquire,relaxed}.

It works on all ppc.

remove volatile of first parameter in __cmpxchg_local and __cmpxchg
Suggested-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NPan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Acked-by: NBoqun Feng <boqun.feng@gmail.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

There are no ibmebus driver that make use of legacy suspend/resume. This
patch removes the support for it from ibmebus framework, new ibmebus
driver (as unlikely as they are) wanting to use suspend/resume should
use dev_pm_ops.

Since there aren't any special bus specific things to do during
suspend/resume and since the PM core will automatically fallback
directly to using the device's PM ops if no bus PM ops are specified
there is no need to have any special ibmebus PM ops at all.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Invoke the kprobe handlers directly rather than through notify_die(), to
reduce path taken for handling kprobes. Similar to commit 6f6343f5
("kprobes/x86: Call exception handlers directly from do_int3/do_debug").

While at it, rename post_kprobe_handler() to kprobe_post_handler() for
more uniform naming.
Reported-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 03465f89 ("powerpc: Use kprobe blacklist for exception
handlers") removed __kprobes annotation from some of the prototypes,
but left the kprobes header include directive unchanged. Remove it as it
is no longer needed.
Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Define and set the POWER9 HFSCR doorbell bit so that guests can use
msgsndp.

ISA 3.0 calls this MSGP, so name it accordingly in the code.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

ISA 3.0 defines a new PECE (Power-saving mode Exit Cause Enable) field
in the LPCR (Logical Partitioning Control Register), called
LPCR_PECE_HVEE (Hypervisor Virtualization Exit Enable).

KVM code will need to know about this bit, so add a definition for it.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

ISA 3.00 adds the logical PVR value 0x0f000005, so add a definition for
this.

Define PCR_ARCH_207 to reflect ISA 2.07 compatibility mode in the processor
compatibility register (PCR).

[paulus@ozlabs.org - moved dummy PCR_ARCH_300 value into next patch]
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This defines real-mode versions of opal_int_get_xirr(), opal_int_eoi()
and opal_int_set_mfrr(), for use by KVM real-mode code.

It also exports opal_int_set_mfrr() so that the modular part of KVM
can use it to send IPIs.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>