Commit Graph

766913 Commits

Author SHA1 Message Date
Hendrik Brueckner
5223c67167 s390/cpum_sf: save TOD clock base in SDBs for time conversion
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: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-31 11:02:27 +02:00
Martin Schwidefsky
03760d44b1 KVM: s390: initial host large page support
- must be enabled via module parameter hpage=1
 - cannot be used together with nested
 - does support migration
 - does support hugetlbfs
 - no THP yet
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Merge tag 'hlp_stage1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into features

Pull hlp_stage1 from Christian Borntraeger with the following changes:

KVM: s390: initial host large page support

- must be enabled via module parameter hpage=1
- cannot be used together with nested
- does support migration
- does support hugetlbfs
- no THP yet
2018-07-31 07:14:19 +02:00
Janosch Frank
a449938297 KVM: s390: Add huge page enablement control
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: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 23:13:38 +02:00
Janosch Frank
a9e00d8349 s390/mm: Add huge page gmap linking support
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: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 23:13:38 +02:00
Dominik Dingel
7d735b9ae8 s390/mm: hugetlb pages within a gmap can not be freed
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: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2018-07-30 23:13:38 +02:00
Janosch Frank
bd096f6443 KVM: s390: Add skey emulation fault handling
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: Janosch Frank <frankja@linux.ibm.com>
2018-07-30 11:20:18 +01:00
Janosch Frank
637ff9efe5 s390/mm: Add huge pmd storage key handling
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: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:18 +01:00
Janosch Frank
3afdfca698 s390/mm: Clear skeys for newly mapped huge guest pmds
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: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-30 11:20:18 +01:00
Dominik Dingel
964c2c05c9 s390/mm: Clear huge page storage keys on enable_skey
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: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
[replaced page_set_storage_key loop with __storage_key_init_range]
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:18 +01:00
Janosch Frank
0959e16867 s390/mm: Add huge page dirty sync support
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: Janosch Frank <frankja@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:18 +01:00
Janosch Frank
6a3762778d s390/mm: Add gmap pmd invalidation and clearing
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: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:17 +01:00
Janosch Frank
7c4b13a7c0 s390/mm: Add gmap pmd notification bit setting
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: Janosch Frank <frankja@linux.ibm.com>
2018-07-30 11:20:17 +01:00
Janosch Frank
58b7e200d2 s390/mm: Add gmap pmd linking
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: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:17 +01:00
Janosch Frank
2c46e974dd s390/mm: Abstract gmap notify bit setting
Currently we use the software PGSTE bits PGSTE_IN_BIT and
PGSTE_VSIE_BIT to notify before an invalidation occurs on a prefix
page or a VSIE page respectively. Both bits are pgste specific, but
are used when protecting a memory range.

Let's introduce abstract GMAP_NOTIFY_* bits that will be realized into
the respective bits when gmap DAT table entries are protected.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 11:20:17 +01:00
Janosch Frank
5a045bb9c4 s390/mm: Make gmap_protect_range more modular
This patch reworks the gmap_protect_range logic and extracts the pte
handling into an own function. Also we do now walk to the pmd and make
it accessible in the function for later use. This way we can add huge
page handling logic more easily.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-30 11:20:17 +01:00
Martin Schwidefsky
6eedfaac71 s390: reenable gcc plugins
Now that the early boot rework is upstream we can enable the gcc plugins
again. See git commit 72f108b308707f21499e0ac05bf7370360cf06d8
"s390: disable gcc plugins" for reference.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-25 09:07:20 +02:00
Martin Schwidefsky
2a6777a118 s390: disable gcc plugins
The s390 build currently fails with the latent entropy plugin:

arch/s390/kernel/als.o: In function `verify_facilities':
als.c:(.init.text+0x24): undefined reference to `latent_entropy'
als.c:(.init.text+0xae): undefined reference to `latent_entropy'
make[3]: *** [arch/s390/boot/compressed/vmlinux] Error 1
make[2]: *** [arch/s390/boot/compressed/vmlinux] Error 2
make[1]: *** [bzImage] Error 2

This will be fixed with the early boot rework from Vasily, which
is planned for the 4.19 merge window.

For 4.18 the simplest solution is to disable the gcc plugins and
reenable them after the early boot rework is upstream.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
(cherry picked from commit 2fba3573f1)
2018-07-25 09:07:09 +02:00
Souptick Joarder
ef4b891f79 s390: vdso_fault return type
Use new return type vm_fault_t for fault handler vdso_fault.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:57 +02:00
Thomas Richter
d1de8633d9 s390 cio: Rewrite trace point class s390_class_schib
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
__field macro for the necessary members.
Keep the __fieldstruct macro to extract the complete
structure when dumps are analysed.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:56 +02:00
Thomas Richter
933df441e7 s390 cio: Rewrite trace point in s390_cio_tsch
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
__field macro for the necessary members.
Keep the __fieldstruct macro to extract the complete
structure when dumps are analysed.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:56 +02:00
Thomas Richter
27c0620ce9 s390 cio: Rewrite trace point in s390_cio_adapter_int
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
__field macro for the necessary members.
Keep the __fieldstruct macro to extract the complete
structure when dumps are analysed.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:55 +02:00
Thomas Richter
67faae1567 s390 cio: Rewrite trace point in s390_cio_stcrw
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
the __field macro for the missing members.
Keep the __fieldstruct macro to extract the complete
structure when dumps are analysed.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:54 +02:00
Thomas Richter
5925e81927 s390 cio: Rewrite trace point in s390_cio_tpi
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
__field macro for the members adapter_IO, isc and type
of struct tpi_info.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:53 +02:00
Thomas Richter
661c959bae s390 cio: Rewrite trace point in s390_cio_interrupt
Tools like 'perf stat' parse the trace point format files defined
in /sys/kernel/debug/tracing/events/s390/.../format to handle
the print fmt: statement. The kernel provides a library in
directory linux/tools/lib/traceevent/* for this reason.

This library can not handle structures or unions defined in
the TRACE_EVENT/TP_STRUCT__entry macros with __field_struct macro.
There is no possibility to extract a structure member
(which might be a bit field) since there is no packing
information nor bit field offset by parsing the printf fmt line.

Therefore rewrite the TRACE_EVENT macro and add the
__field macro for the necessary fields.
Keep the __fieldstruct macro to extract the complete
structure when dumps are analysed.

Note that the same information is displayed, this is no
interface change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-23 13:49:52 +02:00
Gustavo A. R. Silva
cd0ed39dc9 s390/tape: replace PTR_RET with PTR_ERR_OR_ZERO
PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-19 16:37:37 +02:00
Gustavo A. R. Silva
9fa6a659ca s390/hypfs: Replace PTR_RET with PTR_ERR_OR_ZERO
PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-19 16:37:36 +02:00
Gustavo A. R. Silva
757853ea19 s390/dasd: replace PTR_RET with PTR_ERR_OR_ZERO
PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-19 16:37:34 +02:00
Gustavo A. R. Silva
9c705206d0 s390/ap_bus: replace PTR_RET with PTR_ERR_OR_ZERO
PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-19 16:37:33 +02:00
Martin Schwidefsky
054732837c s390/keyboard: sanitize array index in do_kdsk_ioctl
The kbd_ioctl uses two user controlled indexes for KDGKBENT/KDSKBENT.
Use array_index_nospec to prevent any out of bounds speculation.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-19 16:37:30 +02:00
Martin Schwidefsky
aeaf7002a7 s390: detect etoken facility
Detect and report the etoken facility. With spectre_v2=auto or
CONFIG_EXPOLINE_AUTO=y automatically disable expolines and use
the full branch prediction mode for the kernel.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-18 08:32:17 +02:00
Sebastian Ott
ccaabeea02 s390/chsc: fix packed-not-aligned warnings
Remove attribute packed where possible failing this add proper alignment
information to fix warnings like the one below:

drivers/s390/cio/chsc.c: In function 'chsc_siosl':
drivers/s390/cio/chsc.c:1287:2: warning: alignment 1 of 'struct <anonymous>' is less than 4 [-Wpacked-not-aligned]
  } __attribute__ ((packed)) *siosl_area;

Note: this patch should be a nop since non of these structs use auto
storage but allocated pages. However there are changes to the generated
code because of additional padding at the end of some of the structs due
to alignment when memset(foo, 0, sizeof(*foo)) is used.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17 07:27:56 +02:00
Sebastian Ott
d4f5d79e97 s390/css: reduce stsch calls
Both css_evaluate_new_subchannel and cio_validate_subchannel used
stsch and css_sch_is_valid to check for a valid device.

Reduce stsch calls during subchannel evaluation by re-using schib
data. Also the type/devno valid information is only checked once.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17 07:27:55 +02:00
Sebastian Ott
05b217f4c5 s390/css: validate subchannel prior to allocation
In css_alloc_subchannel we allocate the subchannel and do a
validation of the subchannel (to decide if we should look for
devices via this subchannel). On a typical LPAR we find lots
of subchannels to be invalid (because there is no device
attached or the device is blacklisted) leading to lots of
useless kmalloc and kfree calls.

This patch changes the order to only allocate the subchannels
that have been found valid.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17 07:27:54 +02:00
Sebastian Ott
71aa11a40d s390/css: start the subchannel evaluation earlier
The css bus code uses 2 initcalls: channel_subsystem_init to
initialize internal data and channel_subsystem_init_sync to
start scanning for devices and wait for it to finish.

The start scanning for devices part is moved to the first
initcall such that more work happens in parallel.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17 07:27:53 +02:00
Sebastian Ott
87dc8a0128 s390/cio: ensure that a chpid is registered only once
Improve locking in chp_new to make sure that we don't register
the same chpid twice. Chpid registration was synchronized via
the machine check handler thread but we also have codepaths to
look for new chpids triggered independent of that thread (during
IPL or resume from hibernate).

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-17 07:27:51 +02:00
Claudio Imbrenda
306d6c49ac s390/kvm: fix deadlock when killed by oom
When the oom killer kills a userspace process in the page fault handler
while in guest context, the fault handler fails to release the mm_sem
if the FAULT_FLAG_RETRY_NOWAIT option is set. This leads to a deadlock
when tearing down the mm when the process terminates. This bug can only
happen when pfault is enabled, so only KVM clients are affected.

The problem arises in the rare cases in which handle_mm_fault does not
release the mm_sem. This patch fixes the issue by manually releasing
the mm_sem when needed.

Fixes: 24eb3a824c ("KVM: s390: Add FAULT_FLAG_RETRY_NOWAIT for guest fault")
Cc: <stable@vger.kernel.org> # 3.15+
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-16 15:45:46 +02:00
Vasily Gorbik
ac4c4fc87d s390/cmm: avoid add_timer on concurrently used timer
cmm_set_timer could be called concurrently from cmm_thread, cmm proc
handler, upon cmm smsg receive and timer function itself. To avoid
potential race condition and hitting BUG_ON in add_timer on already
pending timer simply reuse mod_timer which is according to
documentation "the only safe way to modify the timeout" with multiple
unserialized concurrent users. mod_timer can handle both active and
inactive timers which allows to carry out minor code simplification as
well.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-16 15:45:41 +02:00
Vasily Gorbik
a09baa9543 s390/crypto: fix gcc 8 stringop-truncation warning
Replace strncpy which is used to deliberately avoid string NUL-termination
with memcpy. This allows to get rid of gcc 8 stringop-truncation warning:

    inlined from 'query_crypto_facility.constprop' at
    drivers/s390/crypto/pkey_api.c:702:2:
./include/linux/string.h:246:9: warning: '__builtin_strncpy' output
truncated before terminating nul copying 8 bytes from a string of the
same length [-Wstringop-truncation]

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-16 15:45:36 +02:00
Dong Jia Shi
9dcc7570b0 MAINTAINERS: Remove myself as maintainer
I am leaving IBM and will move on to other working area,
so remove myself as a vfio-ccw maintainer.

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.ibm.com>

Message-Id: <20180706015743.41810-1-bjsdjshi@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-13 09:08:26 +02:00
Vasily Gorbik
6c8021503f s390/appldata: reuse generic proc handler functions
Simplify appldata proc handlers by reusing generic proc handler functions.

Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:48:08 +02:00
Vasily Gorbik
71e33a1dd7 s390/cmm: split and simplify cmm pages proc handler
Split cmm_pages_handler into cmm_pages_handler and
cmm_timed_pages_handler, each handling separate proc entry.  And reuse
proc_doulongvec_minmax to simplify proc handlers. Min/max values are
optional and are omitted here.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:48:07 +02:00
Vasily Gorbik
196851bed5 s390/topology: correct topology mode proc handler
Reuse proc_douintvec_minmax to simplify topology mode proc handler.
This also enforces correct range of 0-1 on proc writes and correctly
handles numbers starting with 0 or spaces.

Before:
$ echo 01 > /proc/sys/s390/topology
$ cat /proc/sys/s390/topology
0
$ echo ' 1' > /proc/sys/s390/topology
-bash: echo: write error: Invalid argument
$ echo 2 > /proc/sys/s390/topology
-bash: echo: write error: Invalid argument
$ echo 12 > /proc/sys/s390/topology
$ cat /proc/sys/s390/topology
1

After:
$ echo 01 > /proc/sys/s390/topology
$ cat /proc/sys/s390/topology
1
$ echo ' 1' > /proc/sys/s390/topology
$ cat /proc/sys/s390/topology
1
$ echo 2 > /proc/sys/s390/topology
-bash: echo: write error: Invalid argument
$ echo 12 > /proc/sys/s390/topology
-bash: echo: write error: Invalid argument
$ echo '   0' > /proc/sys/s390/topology
$ cat /proc/sys/s390/topology
0

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:53 +02:00
Vasily Gorbik
f149371e9e s390/sclp_async: replace callhome proc handler with generic one
Reuse generic proc_dointvec_minmax proc handler instead of
proc_handler_callhome.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:53 +02:00
Vasily Gorbik
5bedf8aa03 s390/mm: correct allocate_pgste proc_handler callback
Since proc_dointvec does not perform value range control,
proc_dointvec_minmax should be used to limit value range, which is
clearly intended here, as the internal representation of the value:

unsigned int alloc_pgste:1;

In fact it currently works, since we have

      mm->context.alloc_pgste = page_table_allocate_pgste || ...

... since commit 23fefe119c ("s390/kvm: avoid global config of vm.alloc_pgste=1")

Before that it was

       mm->context.alloc_pgste = page_table_allocate_pgste;

which was broken. That was introduced with commit 0b46e0a3ec ("s390/kvm:
remove delayed reallocation of page tables for KVM").

Fixes: 0b46e0a3ec ("s390/kvm: remove delayed reallocation of page tables for KVM")
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:52 +02:00
Philipp Rudo
287d6070ac s390/purgatory: Remove duplicate variable definitions
Currently there are some variables in the purgatory (e.g. kernel_entry)
which are defined twice, once in assembler- and once in c-code. The reason
for this is that these variables are set during purgatory load, where
sanity checks on the corresponding Elf_Sym's are made, while they are used
in assembler-code. Thus adding a second definition in c-code is a handy
workaround to guarantee correct Elf_Sym's are created.

When the purgatory is compiled with -fcommon (default for gcc on s390) this
is no problem because both symbols are merged by the linker. However this
is not required by ISO C and when the purgatory is built with -fno-common
the linker fails with errors like

arch/s390/purgatory/purgatory.o:(.bss+0x18): multiple definition of `kernel_entry'
arch/s390/purgatory/head.o:/.../arch/s390/purgatory/head.S:230: first defined here

Thus remove the duplicate definitions and add the required size and type
information to the assembler definition. Also add -fno-common to the
command line options to prevent similar hacks in the future.

Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:51 +02:00
Philipp Rudo
c315e69308 s390/purgatory: Add missing FORCE to Makefile targets
Without FORCE make does not detect changes only made to the command line
options. So object files might not be re-built even when they should be.
Fix this by adding FORCE where it is missing.

Fixes: 840798a1f5 ("s390/kexec_file: Add purgatory")
Cc: <stable@vger.kernel.org> # 4.17
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:50 +02:00
Philipp Rudo
ad03b821fb s390/purgatory: Fix crash with expoline enabled
When the kernel is built with CONFIG_EXPOLINE=y and a compiler with
indirect branch mitigation enabled the purgatory crashes. The reason for
that is that the macros defined for expoline are used in mem.S. These
macros define new sections (.text.__s390x_indirect_*) which are marked
executable. Due to the missing linker script those sections are linked to
address 0, just as the .text section. In combination with the entry point
also being at address 0 this causes the purgatory load code
(kernel/kexec_file.c: kexec_purgatory_setup_sechdrs) to update the entry
point twice. Thus the old kernel jumps to some 'random' address causing the
crash.

To fix this turn off expolines for the purgatory. There is no problem with
this in this case due to the fact that the purgatory only runs once and the
tlb is purged (diag 308) in the end.

Fixes: 840798a1f5 ("s390/kexec_file: Add purgatory")
Cc: <stable@vger.kernel.org> # 4.17
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-06 08:47:48 +02:00
Kees Cook
ad5728ce21 RAID/s390: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this moves
the "$#" replacement from being an argument to being inside the function,
which avoids generating VLAs.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-04 08:37:50 +02:00
Sebastian Ott
d2f2df6988 s390/dasd: fix cast-function-type warnings
Change the tasklets parameter type to fix W=1 warnings when building
with gcc 8 like below:

drivers/s390/block/dasd.c: In function 'dasd_alloc_device':
drivers/s390/block/dasd.c:129:8: warning: cast between incompatible function types
from 'void (*)(struct dasd_device *)' to 'void (*)(long unsigned int)' [-Wcast-function-type]
        (void (*)(unsigned long)) dasd_device_tasklet,
        ^

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Acked-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-04 08:35:59 +02:00
Sebastian Ott
0ac942826b s390/pci: add fmt3 fmb
Add support for format 3 function measurement blocks.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-04 08:35:58 +02:00