We have to do down_write on the mm semaphore to set a bitfield in the
mm context.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Fixes: a4499382 ("KVM: s390: Add huge page enablement control")
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Copy the key mask to the right offset inside the shadow CRYCB

Fixes: bbeaa58b ("KVM: s390: vsie: support aes dea wrapping keys")
Signed-off-by: NPierre Morel <pmorel@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NJanosch Frank <frankja@linux.ibm.com>
Cc: stable@vger.kernel.org # v4.8+
Message-Id: <1535019956-23539-2-git-send-email-pmorel@linux.ibm.com>
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

We should not return with a lock.
We also have to increase the address when we do page clearing.

Fixes: bd096f64 ("KVM: s390: Add skey emulation fault handling")
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Message-Id: <20180830081355.59234-1-frankja@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The ebcdic.c file contains tables for converting between ebcdic and PC
codepage 437.  I could however not identify which encoding was used for
the comments.  This seems to be some variation of ISO_8859-1 with
non-UTF-8 escape characters.

I have converted this to UTF-8 by manually removing the escape
characters and then running it through recode, to get the same encoding
that we use for the rest of the kernel.

Link: http://lkml.kernel.org/r/20180724111600.4158975-2-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit a0f97e06 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040c ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.

For some reason, LDFLAGS was not renamed.

Using a well-known variable like LDFLAGS may result in accidental
override of the variable.

Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.

I did not touch Makefiles under tools/ since the tools build system
is a different world.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>

git commit cafa0010 ("Raise the minimum required gcc version to 4.6")
raised the minimum gcc version to 4.6. Therefore remove the s390 specific
gcc 4.3 version check, which wasn't sufficient anyway.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Code beautify by following most of the checkpatch suggestions:
 - SPDX license identifier line complains by checkpatch
 - missing space or newline complains by checkpatch
 - octal numbers for permssions complains by checkpatch
 - renaming of static sysfs functions complains by checkpatch
 - fix of block comment complains by checkpatch
 - fix printf like calls where function name instead of %s __func__
   was used
 - __packed instead of __attribute__((packed))
 - init to zero for static variables removed
 - use of DEVICE_ATTR_RO and DEVICE_ATTR_RW macros

No functional code changes or API changes!
Signed-off-by: NHarald Freudenberger <freude@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Function ap_instructions_available() had returntype int but
in fact returned 1 for true and 0 for false. Changed returntype
to bool.
Signed-off-by: NHarald Freudenberger <freude@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

Ref-> commit 1c8f4220 ("mm: change return type to vm_fault_t")

In this patch all the caller of handle_mm_fault() are changed to return
vm_fault_t type.

Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PCSigned-off-by: NSouptick Joarder <jrdr.linux@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: David S. Miller <davem@davemloft.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For this function there are only two users, when 1) the elfcorehdr and 2)
the vmcoreinfo is allocated. However a missing vmcoreinfo is not critical
for kdump. So panicking when it cannot be allocated is not required.

Remove kzalloc_panic and adjust its callers accordingly.
Signed-off-by: NPhilipp Rudo <prudo@linux.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

The vmcoreinfo of a crashed system is potentially fragmented. Thus the
crash kernel has an intermediate step where the vmcoreinfo is copied into a
temporary, continuous buffer in the crash kernel memory. This temporary
buffer is never freed. Free it now to prevent the memleak.

While at it replace all occurrences of "VMCOREINFO" by its corresponding
macro to prevent potential renaming issues.
Signed-off-by: NPhilipp Rudo <prudo@linux.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

There are two ways to pass the vmcoreinfo to the crash kernel 1) via the
os_info mechanism and 2) via the lowcore->vmcore_info field. In the Linux
kernel only the second way is used. However, the first way is ABI for
stand-alone kdump. So other OSes use it to pass additional debug info. Make
the elfcorehdr size calculation aware of both possible ways.

Fixes: 8cce437f ("s390/kdump: Fix elfcorehdr size calculation")
Signed-off-by: NPhilipp Rudo <prudo@linux.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

This information was never useful and is nowadays replaced with
random data. Just get rid of it.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Get rid of a leftover return code in arch_setup_msi_irqs.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

During interrupt setup we allocate interrupt vectors, walk the list of msi
descriptors, and fill in the message data. Requesting more interrupts than
supported on s390 can lead to an out of bounds access.

When we restrict the number of interrupts we should also stop walking the
msi list after all supported interrupts are handled.

Cc: stable@vger.kernel.org
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

During review of KVM patches it was complained that the
ap_instructions_available() function returns 0 if AP
instructions are available and -ENODEV if not. The function
acts like a boolean function to check for AP instructions
available and thus should return 0 on failure and != 0 on
success. Changed to the suggested behaviour and adapted
the one and only caller of this function which is the ap
bus core code.
Signed-off-by: NHarald Freudenberger <freude@linux.ibm.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Utilize -mfentry and -mnop-mcount gcc options together with
-mrecord-mcount to get compiler generated calls to the profiling functions
as nops which are compatible with current -mhotpatch=0,3 approach.  At the
same time -mrecord-mcount enables __mcount_loc section generation by
the compiler which allows to avoid using scripts/recordmcount.pl script.

Link: http://lkml.kernel.org/r/patch-4.thread-aa7b8d.git-aa7b8dbf236f.your-ad-here.call-01533557518-ext-9465@work.hoursReviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Martin's patch 6eedfaac ("s390: reenable gcc plugins") was lost in
the merge commit 85a0b791 ("Merge branch 'for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux") therefore
let's enable gcc plugins again.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

With gcc-8 fsanitize=null become very noisy.  GCC started to complain
about things like &a->b, where 'a' is NULL pointer.  There is no NULL
dereference, we just calculate address to struct member.  It's
technically undefined behavior so UBSAN is correct to report it.  But as
long as there is no real NULL-dereference, I think, we should be fine.

-fno-delete-null-pointer-checks compiler flag should protect us from any
consequences.  So let's just no use -fsanitize=null as it's not useful
for us.  If there is a real NULL-deref we will see crash.  Even if
userspace mapped something at NULL (root can do this), with things like
SMAP should catch the issue.

Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.comSigned-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit c9b5ad54 "s390/mm: tag normal pages vs pages used in page tables"
accidentally changed the logic in arch_set_page_states(), which is used by
the suspend/resume code. set_page_stable(page, order) was changed to
set_page_stable_dat(page, 0). After this, only the first page of higher order
pages will be set to stable, and a write to one of the unstable pages will
result in an addressing exception.

Fix this by using "order" again, instead of "0".

Fixes: c9b5ad54 ("s390/mm: tag normal pages vs pages used in page tables")
Cc: stable@vger.kernel.org # 4.14+
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

For machines without the exrl instruction the BFP jit generates
code that uses an "br %r1" instruction located in the lowcore page.
Unfortunately there is a cut & paste error that puts an additional
"larl %r1,.+14" instruction in the code that clobbers the branch
target address in %r1. Remove the larl instruction.

Cc: <stable@vger.kernel.org> # v4.17+
Fixes: de5cb6eb ("s390: use expoline thunks in the BPF JIT")
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The memove, memset, memcpy, __memset16, __memset32 and __memset64
function have an additional indirect return branch in form of a
"bzr" instruction. These need to use expolines as well.

Cc: <stable@vger.kernel.org> # v4.17+
Fixes: 97489e06 ("s390/lib: use expoline for indirect branches")
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Almost all architectures include it.  Add a ARCH_NO_PREEMPT symbol to
disable preempt support for alpha, hexagon, non-coldfire m68k and
user mode Linux.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Move the source of lib/Kconfig.debug and arch/$(ARCH)/Kconfig.debug to
the top-level Kconfig.  For two architectures that means moving their
arch-specific symbols in that menu into a new arch Kconfig.debug file,
and for a few more creating a dummy file so that we can include it
unconditionally.

Also move the actual 'Kernel hacking' menu to lib/Kconfig.debug, where
it belongs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Instead of duplicating the source statements in every architecture just
do it once in the toplevel Kconfig file.

Note that with this the inclusion of arch/$(SRCARCH/Kconfig moves out of
the top-level Kconfig into arch/Kconfig so that don't violate ordering
constraits while keeping a sensible menu structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The numa_init_early initcall sets the node_to_cpumask_map[0] to the
full cpu_possible_mask. Unfortunately this early_initcall is too late,
the NUMA setup for numa=emu is done even earlier. The order of calls
is numa_setup() -> emu_update_cpu_topology(), then the early_initcalls(),
followed by sched_init_domains().

Starting with git commit 051f3ca0
"sched/topology: Introduce NUMA identity node sched domain"
the incorrect node_to_cpumask_map[0] really screws up the domain
setup and the kernel panics with the follow oops:

Cc: <stable@vger.kernel.org> # v4.15+
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Before the memory for the elfcorehdr is allocated the required size is
estimated with

       alloc_size = 0x1000 + get_cpu_cnt() * 0x4a0 +
               mem_chunk_cnt * sizeof(Elf64_Phdr);

Where 0x4a0 is used as size for the ELF notes to store the register
contend. This size is 8 bytes too small. Usually this does not immediately
cause a problem because the page reserved for overhead (Elf_Ehdr,
vmcoreinfo, etc.) is pretty generous. So usually there is enough spare
memory to counter the mis-calculated per cpu size. However, with growing
overhead and/or a huge cpu count the allocated size gets too small for the
elfcorehdr. Ultimately a BUG_ON is triggered causing the crash kernel to
panic.

Fix this by properly calculating the required size instead of relying on
magic numbers.

Fixes: a62bc073 ("s390/kdump: add support for vector extension")
Signed-off-by: NPhilipp Rudo <prudo@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Processing the samples in the AUX-area by perf requires the computation
of respective time stamps.  The time stamps used by perf are based on
the monotonic clock.  To convert the TOD clock value contained in an
SDB to a monotonic clock value, the TOD clock base is required.  Hence,
also save the TOD clock base in the SDB.
Suggested-by: NThomas Richter <tmricht@linux.ibm.com>
Signed-off-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

General KVM huge page support on s390 has to be enabled via the
kvm.hpage module parameter. Either nested or hpage can be enabled, as
we currently do not support vSIE for huge backed guests. Once the vSIE
support is added we will either drop the parameter or enable it as
default.

For a guest the feature has to be enabled through the new
KVM_CAP_S390_HPAGE_1M capability and the hpage module
parameter. Enabling it means that cmm can't be enabled for the vm and
disables pfmf and storage key interpretation.

This is due to the fact that in some cases, in upcoming patches, we
have to split huge pages in the guest mapping to be able to set more
granular memory protection on 4k pages. These split pages have fake
page tables that are not visible to the Linux memory management which
subsequently will not manage its PGSTEs, while the SIE will. Disabling
these features lets us manage PGSTE data in a consistent matter and
solve that problem.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>

Let's allow huge pmd linking when enabled through the
KVM_CAP_S390_HPAGE_1M capability. Also we can now restrict gmap
invalidation and notification to the cases where the capability has
been activated and save some cycles when that's not the case.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>

Guests backed by huge pages could theoretically free unused pages via
the diagnose 10 instruction. We currently don't allow that, so we
don't have to refault it once it's needed again.
Signed-off-by: NDominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>

Let's introduce an explicit check if skeys have already been enabled
for the vcpu, so we don't have to check the mm context if we don't have
the storage key facility.

This lets us check for enablement without having to take the mm
semaphore and thus speedup skey emulation.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NFarhan Ali <alifm@linux.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

When doing skey emulation for huge guests, we now need to fault in
pmds, as we don't have PGSTES anymore to store them when we do not
have valid table entries.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>

Storage keys for guests with huge page mappings have to be managed in
hardware. There are no PGSTEs for PMDs that we could use to retain the
guests's logical view of the key.
Signed-off-by: NJanosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>

Similarly to the pte skey handling, where we set the storage key to
the default key for each newly mapped pte, we have to also do that for
huge pmds.

With the PG_arch_1 flag we keep track if the area has already been
cleared of its skeys.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

When a guest starts using storage keys, we trap and set a default one
for its whole valid address space. With this patch we are now able to
do that for large pages.

To speed up the storage key insertion, we use
__storage_key_init_range, which in-turn will use sske_frame to set
multiple storage keys with one instruction. As it has been previously
used for debuging we have to get rid of the default key check and make
it quiescing.
Signed-off-by: NDominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: NJanosch Frank <frankja@linux.vnet.ibm.com>
[replaced page_set_storage_key loop with __storage_key_init_range]
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>

To do dirty loging with huge pages, we protect huge pmds in the
gmap. When they are written to, we unprotect them and mark them dirty.

We introduce the function gmap_test_and_clear_dirty_pmd which handles
dirty sync for huge pages.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>

If the host invalidates a pmd, we also have to invalidate the
corresponding gmap pmds, as well as flush them from the TLB. This is
necessary, as we don't share the pmd tables between host and guest as
we do with ptes.

The clearing part of these three new functions sets a guest pmd entry
to _SEGMENT_ENTRY_EMPTY, so the guest will fault on it and we will
re-link it.

Flushing the gmap is not necessary in the host's lazy local and csp
cases. Both purge the TLB completely.
Signed-off-by: NJanosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>

Like for ptes, we also need invalidation notification for pmds, to
make sure the guest lowcore pages are always accessible and later
addition of shadowed pmds.

With PMDs we do not have PGSTEs or some other bits we could use in the
host PMD. Instead we pick one of the free bits in the gmap PMD. Every
time a host pmd will be invalidated, we will check if the respective
gmap PMD has the bit set and in that case fire up the notifier.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>

Let's allow pmds to be linked into gmap for the upcoming s390 KVM huge
page support.

Before this patch we copied the full userspace pmd entry. This is not
correct, as it contains SW defined bits that might be interpreted
differently in the GMAP context. Now we only copy over all hardware
relevant information leaving out the software bits.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>