powerpc/64s/exception: remove H concatenation for EXC_HV variants

Replace all instances of this with gas macros that test the hsrr
parameter and use the appropriate register names / labels.

No gene

powerpc/64s/exception: remove H concatenation for EXC_HV variants

Replace all instances of this with gas macros that test the hsrr
parameter and use the appropriate register names / labels.

No generated code change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Remove extraneous 2nd check for 0xea0 in SOFTEN_TEST]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s/exception: Remove unused SOFTEN_VALUE_0x980

Remove SOFTEN_VALUE_0x980, it's been unused since commit
dabe859ec636 ("powerpc: Give hypervisor decrementer interrupts their
own handler") (S

powerpc/64s/exception: Remove unused SOFTEN_VALUE_0x980

Remove SOFTEN_VALUE_0x980, it's been unused since commit
dabe859ec636 ("powerpc: Give hypervisor decrementer interrupts their
own handler") (Sep 2012).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s/exception: fix line wrap and semicolon inconsistencies in macros

By convention, all lines should be separated by a semicolons. Last line
should have neither semicolon or line wrap.

No g

powerpc/64s/exception: fix line wrap and semicolon inconsistencies in macros

By convention, all lines should be separated by a semicolons. Last line
should have neither semicolon or line wrap.

No generated code change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc/64s: Implement KUAP for Radix MMU

Kernel Userspace Access Prevention utilises a feature of the Radix MMU
which disallows read and write access to userspace addresses. By
utilising this, the

powerpc/64s: Implement KUAP for Radix MMU

Kernel Userspace Access Prevention utilises a feature of the Radix MMU
which disallows read and write access to userspace addresses. By
utilising this, the kernel is prevented from accessing user data from
outside of trusted paths that perform proper safety checks, such as
copy_{to/from}_user() and friends.

Userspace access is disabled from early boot and is only enabled when
performing an operation like copy_{to/from}_user(). The register that
controls this (AMR) does not prevent userspace from accessing itself,
so there is no need to save and restore when entering and exiting
userspace.

When entering the kernel from the kernel we save AMR and if it is not
blocking user access (because eg. we faulted doing a user access) we
reblock user access for the duration of the exception (ie. the page
fault) and then restore the AMR when returning back to the kernel.

This feature can be tested by using the lkdtm driver (CONFIG_LKDTM=y)
and performing the following:

# (echo ACCESS_USERSPACE) > [debugfs]/provoke-crash/DIRECT

If enabled, this should send SIGSEGV to the thread.

We also add paranoid checking of AMR in switch and syscall return
under CONFIG_PPC_KUAP_DEBUG.

Co-authored-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64: Replace CURRENT_THREAD_INFO with PACA_THREAD_INFO

Now that current_thread_info is located at the beginning of 'current'
task struct, CURRENT_THREAD_INFO macro is not really needed any mo

powerpc/64: Replace CURRENT_THREAD_INFO with PACA_THREAD_INFO

Now that current_thread_info is located at the beginning of 'current'
task struct, CURRENT_THREAD_INFO macro is not really needed any more.

This patch replaces it by loads of the value at PACA_THREAD_INFO(r13).

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Add PACA_THREAD_INFO rather than using PACACURRENT]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s/hash: Convert SLB miss handlers to C

This patch moves SLB miss handlers completely to C, using the standard
exception handler macros to set up the stack and branch to C.

This can be don

powerpc/64s/hash: Convert SLB miss handlers to C

This patch moves SLB miss handlers completely to C, using the standard
exception handler macros to set up the stack and branch to C.

This can be done because the segment containing the kernel stack is
always bolted, so accessing it with relocation on will not cause an
SLB exception.

Arbitrary kernel memory must not be accessed when handling kernel
space SLB misses, so care should be taken there. However user SLB
misses can access any kernel memory, which can be used to move some
fields out of the paca (in later patches).

User SLB misses could quite easily reconcile IRQs and set up a first
class kernel environment and exit via ret_from_except, however that
doesn't seem to be necessary at the moment, so we only do that if a
bad fault is encountered.

[ Credit to Aneesh for bug fixes, error checks, and improvements to
bad address handling, etc ]

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Disallow tracing for all of slb.c for now.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64: Interrupts save PPR on stack rather than thread_struct

PPR is the odd register out when it comes to interrupt handling, it is
saved in current->thread.ppr while all others are saved on t

powerpc/64: Interrupts save PPR on stack rather than thread_struct

PPR is the odd register out when it comes to interrupt handling, it is
saved in current->thread.ppr while all others are saved on the stack.

The difficulty with this is that accessing thread.ppr can cause a SLB
fault, but the SLB fault handler implementation in C change had
assumed the normal exception entry handlers would not cause an SLB
fault.

Fix this by allocating room in the interrupt stack to save PPR.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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Revert "convert SLB miss handlers to C" and subsequent commits

This reverts commits:
5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C")
8fed04d0f6ae ("powerpc/64s/hash: remove use

Revert "convert SLB miss handlers to C" and subsequent commits

This reverts commits:
5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C")
8fed04d0f6ae ("powerpc/64s/hash: remove user SLB data from the paca")
655deecf67b2 ("powerpc/64s/hash: SLB allocation status bitmaps")
2e1626744e8d ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup")
89ca4e126a3f ("powerpc/64s/hash: Add a SLB preload cache")

This series had a few bugs, and the fixes are not all trivial. So
revert most of it for now.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s/hash: convert SLB miss handlers to C

This patch moves SLB miss handlers completely to C, using the standard
exception handler macros to set up the stack and branch to C.

This can be don

powerpc/64s/hash: convert SLB miss handlers to C

This patch moves SLB miss handlers completely to C, using the standard
exception handler macros to set up the stack and branch to C.

This can be done because the segment containing the kernel stack is
always bolted, so accessing it with relocation on will not cause an
SLB exception.

Arbitrary kernel memory may not be accessed when handling kernel space
SLB misses, so care should be taken there. However user SLB misses can
access any kernel memory, which can be used to move some fields out of
the paca (in later patches).

User SLB misses could quite easily reconcile IRQs and set up a first
class kernel environment and exit via ret_from_except, however that
doesn't seem to be necessary at the moment, so we only do that if a
bad fault is encountered.

[ Credit to Aneesh for bug fixes, error checks, and improvements to bad
address handling, etc ]

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

Since RFC:
- Added MSR[RI] handling
- Fixed up a register loss bug exposed by irq tracing (Aneesh)
- Reject misses outside the defined kernel regions (Aneesh)
- Added several more sanity checks and error handling (Aneesh), we may
look at consolidating these tests and tightenig up the code but for
a first pass we decided it's better to check carefully.

Since v1:
- Fixed SLB cache corruption (Aneesh)
- Fixed untidy SLBE allocation "leak" in get_vsid error case
- Now survives some stress testing on real hardware

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Drop unused loc parameter to MASKABLE_EXCEPTION macros

We pass the "loc" (location) parameter to MASKABLE_EXCEPTION and
friends, but it's not used, so drop it.

Signed-off-by: Michael E

powerpc/64s: Drop unused loc parameter to MASKABLE_EXCEPTION macros

We pass the "loc" (location) parameter to MASKABLE_EXCEPTION and
friends, but it's not used, so drop it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Remove PSERIES naming from the MASKABLE macros

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Drop _MASKABLE_RELON_EXCEPTION_PSERIES()

_MASKABLE_RELON_EXCEPTION_PSERIES() does nothing useful, update all
callers to use __MASKABLE_RELON_EXCEPTION_PSERIES() directly.

Signed-off-by

powerpc/64s: Drop _MASKABLE_RELON_EXCEPTION_PSERIES()

_MASKABLE_RELON_EXCEPTION_PSERIES() does nothing useful, update all
callers to use __MASKABLE_RELON_EXCEPTION_PSERIES() directly.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Drop _MASKABLE_EXCEPTION_PSERIES()

_MASKABLE_EXCEPTION_PSERIES() does nothing useful, update all callers
to use __MASKABLE_EXCEPTION_PSERIES() directly.

Signed-off-by: Michael Ellerman

powerpc/64s: Drop _MASKABLE_EXCEPTION_PSERIES()

_MASKABLE_EXCEPTION_PSERIES() does nothing useful, update all callers
to use __MASKABLE_EXCEPTION_PSERIES() directly.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Rename EXCEPTION_PROLOG_PSERIES to EXCEPTION_PROLOG

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename EXCEPTION_RELON_PROLOG_PSERIES

To just EXCEPTION_RELON_PROLOG().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename EXCEPTION_RELON_PROLOG_PSERIES_1

The EXCEPTION_RELON_PROLOG_PSERIES_1() macro does the same job as
EXCEPTION_PROLOG_2 (which we just recently created), except for
"RELON" (reloca

powerpc/64s: Rename EXCEPTION_RELON_PROLOG_PSERIES_1

The EXCEPTION_RELON_PROLOG_PSERIES_1() macro does the same job as
EXCEPTION_PROLOG_2 (which we just recently created), except for
"RELON" (relocation on) exceptions.

So rename it as such.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Remove PSERIES from the NORI macros

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename EXCEPTION_PROLOG_PSERIES_1 to EXCEPTION_PROLOG_2

As with the other patches in this series, we are removing the
"PSERIES" from the name as it's no longer meaningful.

In this case

powerpc/64s: Rename EXCEPTION_PROLOG_PSERIES_1 to EXCEPTION_PROLOG_2

As with the other patches in this series, we are removing the
"PSERIES" from the name as it's no longer meaningful.

In this case it's not simply a case of removing the "PSERIES" as that
would result in a clash with the existing EXCEPTION_PROLOG_1.

Instead we name this one EXCEPTION_PROLOG_2, as it's usually used in
sequence after 0 and 1.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Rename STD_RELON_EXCEPTION_PSERIES_OOL to STD_RELON_EXCEPTION_OOL

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename STD_RELON_EXCEPTION_PSERIES to STD_RELON_EXCEPTION

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename STD_EXCEPTION_PSERIES_OOL to STD_EXCEPTION_OOL

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64s: Rename STD_EXCEPTION_PSERIES to STD_EXCEPTION

The "PSERIES" in STD_EXCEPTION_PSERIES is to differentiate the macros
from the legacy iSeries versions, which are called
STD_EXCEPTION_ISER

powerpc/64s: Rename STD_EXCEPTION_PSERIES to STD_EXCEPTION

The "PSERIES" in STD_EXCEPTION_PSERIES is to differentiate the macros
from the legacy iSeries versions, which are called
STD_EXCEPTION_ISERIES. It is not anything to do with pseries vs
powernv or powermac etc.

We removed the legacy iSeries code in 2012, in commit 8ee3e0d69623x
("powerpc: Remove the main legacy iSerie platform code").

So remove "PSERIES" from the macros.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Move SET_SCRATCH0() into EXCEPTION_RELON_PROLOG_PSERIES()

EXCEPTION_RELON_PROLOG_PSERIES() only has two users,
STD_RELON_EXCEPTION_PSERIES() and STD_RELON_EXCEPTION_HV() both of
which "

powerpc/64s: Move SET_SCRATCH0() into EXCEPTION_RELON_PROLOG_PSERIES()

EXCEPTION_RELON_PROLOG_PSERIES() only has two users,
STD_RELON_EXCEPTION_PSERIES() and STD_RELON_EXCEPTION_HV() both of
which "call" SET_SCRATCH0(), so just move SET_SCRATCH0() into
EXCEPTION_RELON_PROLOG_PSERIES().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/64s: Move SET_SCRATCH0() into EXCEPTION_PROLOG_PSERIES()

EXCEPTION_PROLOG_PSERIES() only has two users, STD_EXCEPTION_PSERIES()
and STD_EXCEPTION_HV() both of which "call" SET_SCRATCH0(), so

powerpc/64s: Move SET_SCRATCH0() into EXCEPTION_PROLOG_PSERIES()

EXCEPTION_PROLOG_PSERIES() only has two users, STD_EXCEPTION_PSERIES()
and STD_EXCEPTION_HV() both of which "call" SET_SCRATCH0(), so just
move SET_SCRATCH0() into EXCEPTION_PROLOG_PSERIES().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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