linux-stable.git/arch/powerpc/kernel, branch v4.4.151

powerpc/8xx: fix invalid register expression in head_8xx.S

2018-08-06T14:24:34+00:00

[ Upstream commit e4ccb1dae6bdef228d729c076c38161ef6e7ca34 ]

New binutils generate the following warning

  AS      arch/powerpc/kernel/head_8xx.o
arch/powerpc/kernel/head_8xx.S: Assembler messages:
arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression

This patch fixes it.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

powerpc/32: Add a missing include header

2018-08-06T14:24:34+00:00

[ Upstream commit c89ca593220931c150cffda24b4d4ccf82f13fc8 ]

The header file  was missing from the includes. Fix the
following warning, treated as error with W=1:

  arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes]

Signed-off-by: Mathieu Malaterre 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

powerpc/fadump: Unregister fadump on kexec down path.

2018-07-03T09:21:29+00:00

commit 722cde76d68e8cc4f3de42e71c82fd40dea4f7b9 upstream.

Unregister fadump on kexec down path otherwise the fadump registration
in new kexec-ed kernel complains that fadump is already registered.
This makes new kernel to continue using fadump registered by previous
kernel which may lead to invalid vmcore generation. Hence this patch
fixes this issue by un-registering fadump in fadump_cleanup() which is
called during kexec path so that new kernel can register fadump with
new valid values.

Fixes: b500afff11f6 ("fadump: Invalidate registration and release reserved memory for general use.")
Cc: stable@vger.kernel.org # v3.4+
Signed-off-by: Mahesh Salgaonkar 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/ptrace: Fix enforcement of DAWR constraints

2018-07-03T09:21:29+00:00

commit cd6ef7eebf171bfcba7dc2df719c2a4958775040 upstream.

Back when we first introduced the DAWR, in commit 4ae7ebe9522a
("powerpc: Change hardware breakpoint to allow longer ranges"), we
screwed up the constraint making it a 1024 byte boundary rather than a
512. This makes the check overly permissive. Fortunately GDB is the
only real user and it always did they right thing, so we never
noticed.

This fixes the constraint to 512 bytes.

Fixes: 4ae7ebe9522a ("powerpc: Change hardware breakpoint to allow longer ranges")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG

2018-07-03T09:21:28+00:00

commit 4f7c06e26ec9cf7fe9f0c54dc90079b6a4f4b2c3 upstream.

In commit e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when
validating DAWR region end") we fixed setting the DAWR end point to
its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke
PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint.

PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to
zero (memset() in hw_breakpoint_init()). This worked with
arch_validate_hwbkpt_settings() before the above patch was applied but
is now broken if the breakpoint is 512byte aligned.

This sets the length of the breakpoint to 8 bytes when using
PTRACE_SET_DEBUGREG.

Fixes: e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when validating DAWR region end")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Michael Neuling 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/mm/hash: Add missing isync prior to kernel stack SLB switch

2018-07-03T09:21:28+00:00

commit 91d06971881f71d945910de128658038513d1b24 upstream.

Currently we do not have an isync, or any other context synchronizing
instruction prior to the slbie/slbmte in _switch() that updates the
SLB entry for the kernel stack.

However that is not correct as outlined in the ISA.

From Power ISA Version 3.0B, Book III, Chapter 11, page 1133:

  "Changing the contents of ... the contents of SLB entries ... can
   have the side effect of altering the context in which data
   addresses and instruction addresses are interpreted, and in which
   instructions are executed and data accesses are performed.
   ...
   These side effects need not occur in program order, and therefore
   may require explicit synchronization by software.
   ...
   The synchronizing instruction before the context-altering
   instruction ensures that all instructions up to and including that
   synchronizing instruction are fetched and executed in the context
   that existed before the alteration."

And page 1136:

  "For data accesses, the context synchronizing instruction before the
   slbie, slbieg, slbia, slbmte, tlbie, or tlbiel instruction ensures
   that all preceding instructions that access data storage have
   completed to a point at which they have reported all exceptions
   they will cause."

We're not aware of any bugs caused by this, but it should be fixed
regardless.

Add the missing isync when updating kernel stack SLB entry.

Cc: stable@vger.kernel.org
Signed-off-by: Aneesh Kumar K.V 
[mpe: Flesh out change log with more ISA text & explanation]
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/64s: Clear PCR on boot

2018-06-06T14:46:20+00:00

commit faf37c44a105f3608115785f17cbbf3500f8bc71 upstream.

Clear the PCR (Processor Compatibility Register) on boot to ensure we
are not running in a compatibility mode.

We've seen this cause problems when a crash (and kdump) occurs while
running compat mode guests. The kdump kernel then runs with the PCR
set and causes problems. The symptom in the kdump kernel (also seen in
petitboot after fast-reboot) is early userspace programs taking
sigills on newer instructions (seen in libc).

Signed-off-by: Michael Neuling 
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc: Don't preempt_disable() in show_cpuinfo()

2018-05-26T06:48:53+00:00

commit 349524bc0da698ec77f2057cf4a4948eb6349265 upstream.

This causes warnings from cpufreq mutex code. This is also rather
unnecessary and ineffective. If we really want to prevent concurrent
unplug, we could take the unplug read lock but I don't see this being
critical.

Fixes: cd77b5ce208c ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo")
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman 
Acked-by: Michal Suchanek 
Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Fix enabling bridge MMIO windows

2018-04-24T07:32:11+00:00

commit 13a83eac373c49c0a081cbcd137e79210fe78acd upstream.

On boot we save the configuration space of PCIe bridges. We do this so
when we get an EEH event and everything gets reset that we can restore
them.

Unfortunately we save this state before we've enabled the MMIO space
on the bridges. Hence if we have to reset the bridge when we come back
MMIO is not enabled and we end up taking an PE freeze when the driver
starts accessing again.

This patch forces the memory/MMIO and bus mastering on when restoring
bridges on EEH. Ideally we'd do this correctly by saving the
configuration space writes later, but that will have to come later in
a larger EEH rewrite. For now we have this simple fix.

The original bug can be triggered on a boston machine by doing:
  echo 0x8000000000000000 > /sys/kernel/debug/powerpc/PCI0001/err_injct_outbound
On boston, this PHB has a PCIe switch on it.  Without this patch,
you'll see two EEH events, 1 expected and 1 the failure we are fixing
here. The second EEH event causes the anything under the PHB to
disappear (i.e. the i40e eth).

With this patch, only 1 EEH event occurs and devices properly recover.

Fixes: 652defed4875 ("powerpc/eeh: Check PCIe link after reset")
Cc: stable@vger.kernel.org # v3.11+
Reported-by: Pridhiviraj Paidipeddi 
Signed-off-by: Michael Neuling 
Acked-by: Russell Currey 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/[booke|4xx]: Don't clobber TCR[WP] when setting TCR[DIE]

2018-04-13T17:50:14+00:00

[ Upstream commit 6e2f03e292ef46eed2b31b0a344a91d514f9cd81 ]

Prevent a kernel panic caused by unintentionally clearing TCR watchdog
bits. At this point in the kernel boot, the watchdog may have already
been enabled by u-boot. The original code's attempt to write to the TCR
register results in an inadvertent clearing of the watchdog
configuration bits, causing the 476 to reset.

Signed-off-by: Ivan Mikhaylov 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman