Since there is no interception for load control and load psw
instruction in the protected mode, we need a new way to get notified
whenever we can inject an IRQ right after the guest has just enabled
the possibility for receiving them.
The new interception codes solve that problem by providing a
notification for changes to IRQ enablement relevant bits in CRs 0, 6
and 14, as well a the machine check mask bit in the PSW.
No special handling is needed for these interception codes, the KVM
pre-run code will consult all necessary CRs and PSW bits and inject
IRQs the guest is enabled for.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Before we destroy the secure configuration, we better make all
pages accessible again. This also happens during reboot, where we reboot
into a non-secure guest that then can go again into secure mode. As
this "new" secure guest will have a new ID we cannot reuse the old page
state.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
KSM will not work on secure pages, because when the kernel reads a
secure page, it will be encrypted and hence no two pages will look the
same.
Let's mark the guest pages as unmergeable when we transition to secure
mode.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This contains 3 main changes:
1. changes in SIE control block handling for secure guests
2. helper functions for create/destroy/unpack secure guests
3. KVM_S390_PV_COMMAND ioctl to allow userspace dealing with secure
machines
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This adds two new helper functions for doing UV CALLs.
The first variant handles UV CALLs that might have longer busy
conditions or just need longer when doing partial completion. We should
schedule when necessary.
The second variant handles UV CALLs that only need the handle but have
no payload (e.g. destroying a VM). We can provide a simple wrapper for
those.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The adapter interrupt page containing the indicator bits is currently
pinned. That means that a guest with many devices can pin a lot of
memory pages in the host. This also complicates the reference tracking
which is needed for memory management handling of protected virtual
machines. It might also have some strange side effects for madvise
MADV_DONTNEED and other things.
We can simply try to get the userspace page set the bits and free the
page. By storing the userspace address in the irq routing entry instead
of the guest address we can actually avoid many lookups and list walks
so that this variant is very likely not slower.
If userspace messes around with the memory slots the worst thing that
can happen is that we write to some other memory within that process.
As we get the the page with FOLL_WRITE this can also not be used to
write to shared read-only pages.
Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch simplification]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This provides the basic ultravisor calls and page table handling to cope
with secure guests:
- provide arch_make_page_accessible
- make pages accessible after unmapping of secure guests
- provide the ultravisor commands convert to/from secure
- provide the ultravisor commands pin/unpin shared
- provide callbacks to make pages secure (inacccessible)
- we check for the expected pin count to only make pages secure if the
host is not accessing them
- we fence hugetlbfs for secure pages
- add missing radix-tree include into gmap.h
The basic idea is that a page can have 3 states: secure, normal or
shared. The hypervisor can call into a firmware function called
ultravisor that allows to change the state of a page: convert from/to
secure. The convert from secure will encrypt the page and make it
available to the host and host I/O. The convert to secure will remove
the host capability to access this page.
The design is that on convert to secure we will wait until writeback and
page refs are indicating no host usage. At the same time the convert
from secure (export to host) will be called in common code when the
refcount or the writeback bit is already set. This avoids races between
convert from and to secure.
Then there is also the concept of shared pages. Those are kind of secure
where the host can still access those pages. We need to be notified when
the guest "unshares" such a page, basically doing a convert to secure by
then. There is a call "pin shared page" that we use instead of convert
from secure when possible.
We do use PG_arch_1 as an optimization to minimize the convert from
secure/pin shared.
Several comments have been added in the code to explain the logic in
the relevant places.
Co-developed-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Before being able to host protected virtual machines, donate some of
the memory to the ultravisor. Besides that the ultravisor might impose
addressing limitations for memory used to back protected VM storage. Treat
that limit as protected virtualization host's virtual memory limit.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.
Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
It turned out that fake numa support is rather useless on s390, since
there are no scenarios where there is any performance or other benefit
when used.
However it does provide maintenance cost and breaks from time to time.
Therefore remove it.
CONFIG_NUMA is still supported with a very small backend and only one
node. This way userspace applications which require NUMA interfaces
continue to work.
Note that NODES_SHIFT is set to 1 (= 2 nodes) instead of 0 (= 1 node),
since there is quite a bit of kernel code which assumes that more than
one node is possible if CONFIG_NUMA is enabled.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
sbale->addr holds an absolute address (or for some FCP usage, an opaque
request ID), and should only be used with proper virt/phys translation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
As the comment says, sl->sbal holds an absolute address. qeth currently
solves this through wild casting, while zfcp doesn't care.
Handle this properly in the code that actually builds the SL.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com> [for qdio]
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
s390 math emulation was removed with commit 5a79859ae0 ("s390:
remove 31 bit support"), rendering ieee_emulation_warnings useless.
The code still built because it was protected by CONFIG_MATHEMU, which
was no longer selectable.
This patch removes the sysctl_ieee_emulation_warnings declaration and
the sysctl entry declaration.
Link: https://lkml.kernel.org/r/20200214172628.3598516-1-steve@sk2.org
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Clang warns:
In file included from ../arch/s390/purgatory/purgatory.c:10:
In file included from ../include/linux/kexec.h:18:
In file included from ../include/linux/crash_core.h:6:
In file included from ../include/linux/elfcore.h:5:
In file included from ../include/linux/user.h:1:
In file included from ../arch/s390/include/asm/user.h:11:
../arch/s390/include/asm/page.h:45:6: warning: converting the result of
'<<' to a boolean always evaluates to false
[-Wtautological-constant-compare]
if (PAGE_DEFAULT_KEY)
^
../arch/s390/include/asm/page.h:23:44: note: expanded from macro
'PAGE_DEFAULT_KEY'
#define PAGE_DEFAULT_KEY (PAGE_DEFAULT_ACC << 4)
^
1 warning generated.
Explicitly compare this against zero to silence the warning as it is
intended to be used in a boolean context.
Fixes: de3fa841e4 ("s390/mm: fix compile for PAGE_DEFAULT_KEY != 0")
Link: https://github.com/ClangBuiltLinux/linux/issues/860
Link: https://lkml.kernel.org/r/20200214064207.10381-1-natechancellor@gmail.com
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Clang warns:
In file included from ../arch/s390/boot/startup.c:3:
In file included from ../include/linux/elf.h:5:
In file included from ../arch/s390/include/asm/elf.h:132:
In file included from ../include/linux/compat.h:10:
In file included from ../include/linux/time.h:74:
In file included from ../include/linux/time32.h:13:
In file included from ../include/linux/timex.h:65:
../arch/s390/include/asm/timex.h:160:20: warning: passing 'unsigned char
[16]' to parameter of type 'char *' converts between pointers to integer
types with different sign [-Wpointer-sign]
get_tod_clock_ext(clk);
^~~
../arch/s390/include/asm/timex.h:149:44: note: passing argument to
parameter 'clk' here
static inline void get_tod_clock_ext(char *clk)
^
Change clk's type to just be char so that it matches what happens in
get_tod_clock_ext.
Fixes: 57b28f6631 ("[S390] s390_hypfs: Add new attributes")
Link: https://github.com/ClangBuiltLinux/linux/issues/861
Link: http://lkml.kernel.org/r/20200208140858.47970-1-natechancellor@gmail.com
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull more KVM updates from Paolo Bonzini:
"s390:
- fix register corruption
- ENOTSUPP/EOPNOTSUPP mixed
- reset cleanups/fixes
- selftests
x86:
- Bug fixes and cleanups
- AMD support for APIC virtualization even in combination with
in-kernel PIT or IOAPIC.
MIPS:
- Compilation fix.
Generic:
- Fix refcount overflow for zero page"
* tag 'kvm-5.6-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
KVM: vmx: delete meaningless vmx_decache_cr0_guest_bits() declaration
KVM: x86: Mark CR4.UMIP as reserved based on associated CPUID bit
x86: vmxfeatures: rename features for consistency with KVM and manual
KVM: SVM: relax conditions for allowing MSR_IA32_SPEC_CTRL accesses
KVM: x86: Fix perfctr WRMSR for running counters
x86/kvm/hyper-v: don't allow to turn on unsupported VMX controls for nested guests
x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()
kvm: mmu: Separate generating and setting mmio ptes
kvm: mmu: Replace unsigned with unsigned int for PTE access
KVM: nVMX: Remove stale comment from nested_vmx_load_cr3()
KVM: MIPS: Fold comparecount_func() into comparecount_wakeup()
KVM: MIPS: Fix a build error due to referencing not-yet-defined function
x86/kvm: do not setup pv tlb flush when not paravirtualized
KVM: fix overflow of zero page refcount with ksm running
KVM: x86: Take a u64 when checking for a valid dr7 value
KVM: x86: use raw clock values consistently
KVM: x86: reorganize pvclock_gtod_data members
KVM: nVMX: delete meaningless nested_vmx_run() declaration
KVM: SVM: allow AVIC without split irqchip
kvm: ioapic: Lazy update IOAPIC EOI
...
Pull more s390 updates from Vasily Gorbik:
"The second round of s390 fixes and features for 5.6:
- Add KPROBES_ON_FTRACE support
- Add EP11 AES secure keys support
- PAES rework and prerequisites for paes-s390 ciphers selftests
- Fix page table upgrade for hugetlbfs"
* tag 's390-5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/pkey/zcrypt: Support EP11 AES secure keys
s390/zcrypt: extend EP11 card and queue sysfs attributes
s390/zcrypt: add new low level ep11 functions support file
s390/zcrypt: ep11 structs rework, export zcrypt_send_ep11_cprb
s390/zcrypt: enable card/domain autoselect on ep11 cprbs
s390/crypto: enable clear key values for paes ciphers
s390/pkey: Add support for key blob with clear key value
s390/crypto: Rework on paes implementation
s390: support KPROBES_ON_FTRACE
s390/mm: fix dynamic pagetable upgrade for hugetlbfs
Pull Microblaze update from Michal Simek:
- enable CMA
- add support for MB v11
- defconfig updates
- minor fixes
* tag 'microblaze-v5.6-rc1' of git://git.monstr.eu/linux-2.6-microblaze:
microblaze: Add ID for Microblaze v11
microblaze: Prevent the overflow of the start
microblaze: Wire CMA allocator
asm-generic: Make dma-contiguous.h a mandatory include/asm header
microblaze: Sync defconfig with latest Kconfig layout
microblaze: defconfig: Disable EXT2 driver and Enable EXT3 & EXT4 drivers
microblaze: Align comments with register usage
Pull random changes from Ted Ts'o:
"Change /dev/random so that it uses the CRNG and only blocking if the
CRNG hasn't initialized, instead of the old blocking pool. Also clean
up archrandom.h, and some other miscellaneous cleanups"
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (24 commits)
s390x: Mark archrandom.h functions __must_check
powerpc: Mark archrandom.h functions __must_check
powerpc: Use bool in archrandom.h
x86: Mark archrandom.h functions __must_check
linux/random.h: Mark CONFIG_ARCH_RANDOM functions __must_check
linux/random.h: Use false with bool
linux/random.h: Remove arch_has_random, arch_has_random_seed
s390: Remove arch_has_random, arch_has_random_seed
powerpc: Remove arch_has_random, arch_has_random_seed
x86: Remove arch_has_random, arch_has_random_seed
random: remove some dead code of poolinfo
random: fix typo in add_timer_randomness()
random: Add and use pr_fmt()
random: convert to ENTROPY_BITS for better code readability
random: remove unnecessary unlikely()
random: remove kernel.random.read_wakeup_threshold
random: delete code to pull data into pools
random: remove the blocking pool
random: make /dev/random be almost like /dev/urandom
random: ignore GRND_RANDOM in getentropy(2)
...
Pull updates from Andrew Morton:
"Most of -mm and quite a number of other subsystems: hotfixes, scripts,
ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov.
MM is fairly quiet this time. Holidays, I assume"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
kcov: ignore fault-inject and stacktrace
include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc()
execve: warn if process starts with executable stack
reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()
init/main.c: fix misleading "This architecture does not have kernel memory protection" message
init/main.c: fix quoted value handling in unknown_bootoption
init/main.c: remove unnecessary repair_env_string in do_initcall_level
init/main.c: log arguments and environment passed to init
fs/binfmt_elf.c: coredump: allow process with empty address space to coredump
fs/binfmt_elf.c: coredump: delete duplicated overflow check
fs/binfmt_elf.c: coredump: allocate core ELF header on stack
fs/binfmt_elf.c: make BAD_ADDR() unlikely
fs/binfmt_elf.c: better codegen around current->mm
fs/binfmt_elf.c: don't copy ELF header around
fs/binfmt_elf.c: fix ->start_code calculation
fs/binfmt_elf.c: smaller code generation around auxv vector fill
lib/find_bit.c: uninline helper _find_next_bit()
lib/find_bit.c: join _find_next_bit{_le}
uapi: rename ext2_swab() to swab() and share globally in swab.h
lib/scatterlist.c: adjust indentation in __sg_alloc_table
...
Pull KVM updates from Paolo Bonzini:
"This is the first batch of KVM changes.
ARM:
- cleanups and corner case fixes.
PPC:
- Bugfixes
x86:
- Support for mapping DAX areas with large nested page table entries.
- Cleanups and bugfixes here too. A particularly important one is a
fix for FPU load when the thread has TIF_NEED_FPU_LOAD. There is
also a race condition which could be used in guest userspace to
exploit the guest kernel, for which the embargo expired today.
- Fast path for IPI delivery vmexits, shaving about 200 clock cycles
from IPI latency.
- Protect against "Spectre-v1/L1TF" (bring data in the cache via
speculative out of bound accesses, use L1TF on the sibling
hyperthread to read it), which unfortunately is an even bigger
whack-a-mole game than SpectreV1.
Sean continues his mission to rewrite KVM. In addition to a sizable
number of x86 patches, this time he contributed a pretty large
refactoring of vCPU creation that affects all architectures but should
not have any visible effect.
s390 will come next week together with some more x86 patches"
* tag 'kvm-5.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
x86/KVM: Clean up host's steal time structure
x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed
x86/kvm: Cache gfn to pfn translation
x86/kvm: Introduce kvm_(un)map_gfn()
x86/kvm: Be careful not to clear KVM_VCPU_FLUSH_TLB bit
KVM: PPC: Book3S PR: Fix -Werror=return-type build failure
KVM: PPC: Book3S HV: Release lock on page-out failure path
KVM: arm64: Treat emulated TVAL TimerValue as a signed 32-bit integer
KVM: arm64: pmu: Only handle supported event counters
KVM: arm64: pmu: Fix chained SW_INCR counters
KVM: arm64: pmu: Don't mark a counter as chained if the odd one is disabled
KVM: arm64: pmu: Don't increment SW_INCR if PMCR.E is unset
KVM: x86: Use a typedef for fastop functions
KVM: X86: Add 'else' to unify fastop and execute call path
KVM: x86: inline memslot_valid_for_gpte
KVM: x86/mmu: Use huge pages for DAX-backed files
KVM: x86/mmu: Remove lpage_is_disallowed() check from set_spte()
KVM: x86/mmu: Fold max_mapping_level() into kvm_mmu_hugepage_adjust()
KVM: x86/mmu: Zap any compound page when collapsing sptes
KVM: x86/mmu: Remove obsolete gfn restoration in FNAME(fetch)
...
Instead of using our own kprobes-on-ftrace handling convert the
code to support KPROBES_ON_FTRACE.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Commit ee71d16d22 ("s390/mm: make TASK_SIZE independent from the number
of page table levels") changed the logic of TASK_SIZE and also removed the
arch_mmap_check() implementation for s390. This combination has a subtle
effect on how get_unmapped_area() for hugetlbfs pages works. It is now
possible that a user process establishes a hugetlbfs mapping at an address
above 4 TB, without triggering a dynamic pagetable upgrade from 3 to 4
levels.
This is because hugetlbfs mappings will not use mm->get_unmapped_area, but
rather file->f_op->get_unmapped_area, which currently is the generic
implementation of hugetlb_get_unmapped_area() that does not know about s390
dynamic pagetable upgrades, but with the new definition of TASK_SIZE, it
will now allow mappings above 4 TB.
Subsequent access to such a mapped address above 4 TB will result in a page
fault loop, because the CPU cannot translate such a large address with 3
pagetable levels. The fault handler will try to map in a hugepage at the
address, but due to the folded pagetable logic it will end up with creating
entries in the 3 level pagetable, possibly overwriting existing mappings,
and then it all repeats when the access is retried.
Apart from the page fault loop, this can have various nasty effects, e.g.
kernel panic from one of the BUG_ON() checks in memory management code,
or even data loss if an existing mapping gets overwritten.
Fix this by implementing HAVE_ARCH_HUGETLB_UNMAPPED_AREA support for s390,
providing an s390 version for hugetlb_get_unmapped_area() with pagetable
upgrade support similar to arch_get_unmapped_area(), which will then be
used instead of the generic version.
Fixes: ee71d16d22 ("s390/mm: make TASK_SIZE independent from the number of page table levels")
Cc: <stable@vger.kernel.org> # 4.12+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull SCSI updates from James Bottomley:
"This series is slightly unusual because it includes Arnd's compat
ioctl tree here:
1c46a2cf2d Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue
Excluding Arnd's changes, this is mostly an update of the usual
drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.
There are a couple of core and base updates around error propagation
and atomicity in the attribute container base we use for the SCSI
transport classes.
The rest is minor changes and updates"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits)
scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask
scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity
scsi: hisi_sas: Modify the file permissions of trigger_dump to write only
scsi: hisi_sas: Replace magic number when handle channel interrupt
scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock
scsi: hisi_sas: use threaded irq to process CQ interrupts
scsi: ufs: Use UFS device indicated maximum LU number
scsi: ufs: Add max_lu_supported in struct ufs_dev_info
scsi: ufs: Delete is_init_prefetch from struct ufs_hba
scsi: ufs: Inline two functions into their callers
scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init()
scsi: ufs: Split ufshcd_probe_hba() based on its called flow
scsi: ufs: Delete struct ufs_dev_desc
scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails
scsi: ufs-mediatek: enable low-power mode for hibern8 state
scsi: ufs: export some functions for vendor usage
scsi: ufs-mediatek: add dbg_register_dump implementation
scsi: qla2xxx: Fix a NULL pointer dereference in an error path
scsi: qla1280: Make checking for 64bit support consistent
scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1
...
Pull s390 updates from Vasily Gorbik:
- Add clang 10 build support.
- Fix BUG() implementation to contain precise bug address, which is
relevant for kprobes.
- Make ftraced function appear in a stacktrace.
- Minor perf improvements and refactoring.
- Possible deadlock and recovery fixes in pci code.
* tag 's390-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: fix __EMIT_BUG() macro
s390/ftrace: generate traced function stack frame
s390: adjust -mpacked-stack support check for clang 10
s390/jump_label: use "i" constraint for clang
s390/cpum_sf: Use DIV_ROUND_UP
s390/cpum_sf: Use kzalloc and minor changes
s390/cpum_sf: Convert debug trace to common layout
s390/pci: Fix possible deadlock in recover_store()
s390/pci: Recover handle in clp_set_pci_fn()
Pull scheduler updates from Ingo Molnar:
"These were the main changes in this cycle:
- More -rt motivated separation of CONFIG_PREEMPT and
CONFIG_PREEMPTION.
- Add more low level scheduling topology sanity checks and warnings
to filter out nonsensical topologies that break scheduling.
- Extend uclamp constraints to influence wakeup CPU placement
- Make the RT scheduler more aware of asymmetric topologies and CPU
capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y
- Make idle CPU selection more consistent
- Various fixes, smaller cleanups, updates and enhancements - please
see the git log for details"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
sched/fair: Define sched_idle_cpu() only for SMP configurations
sched/topology: Assert non-NUMA topology masks don't (partially) overlap
idle: fix spelling mistake "iterrupts" -> "interrupts"
sched/fair: Remove redundant call to cpufreq_update_util()
sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
sched/fair: calculate delta runnable load only when it's needed
sched/cputime: move rq parameter in irqtime_account_process_tick
stop_machine: Make stop_cpus() static
sched/debug: Reset watchdog on all CPUs while processing sysrq-t
sched/core: Fix size of rq::uclamp initialization
sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
sched/fair: Load balance aggressively for SCHED_IDLE CPUs
sched/fair : Improve update_sd_pick_busiest for spare capacity case
watchdog: Remove soft_lockup_hrtimer_cnt and related code
sched/rt: Make RT capacity-aware
sched/fair: Make EAS wakeup placement consider uclamp restrictions
sched/fair: Make task_fits_capacity() consider uclamp restrictions
sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
sched/uclamp: Make uclamp util helpers use and return UL values
...
Setting a kprobe on getname_flags() failed:
$ echo 'p:tmr1 getname_flags +0(%r2):ustring' > kprobe_events
-bash: echo: write error: Invalid argument
Debugging the kprobes code showed that the address of
getname_flags() is contained in the __bug_table. Kprobes
doesn't allow to set probes at BUG() locations.
$ objdump -j __bug_table -x build/fs/namei.o
[..]
0000000000000108 R_390_PC32 .text+0x00000000000075a8
000000000000010c R_390_PC32 .L223+0x0000000000000004
I was expecting getname_flags() to start with a BUG(), but:
7598: e3 20 10 00 00 04 lg %r2,0(%r1)
759e: c0 f4 00 00 00 00 jg 759e <putname+0x7e>
75a0: R_390_PLT32DBL kmem_cache_free+0x2
75a4: a7 f4 00 01 j 75a6 <putname+0x86>
00000000000075a8 <getname_flags>:
75a8: c0 04 00 00 00 00 brcl 0,75a8 <getname_flags>
75ae: eb 6f f0 48 00 24 stmg %r6,%r15,72(%r15)
75b4: b9 04 00 ef lgr %r14,%r15
75b8: e3 f0 ff a8 ff 71 lay %r15,-88(%r15)
So the BUG() is actually the last opcode of the previous function.
Fix this by switching to using the MONITOR CALL (MC) instruction,
and set the entry in __bug_table to the beginning of that MC.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Currently kernel build fails under clang if jump labels are enabled.
The problem is "X" constraint usage "Any operand whatsoever is allowed",
for which clang produces the following:
.pushsection __jump_table,"aw"
.balign 8
.long 0b-.,.Ltmp577-.
.quad %r0+0-. # %r0 is not allowed here
.popsection
Under gcc constraints "X" or "jdd" (gcc > 9) are used for static keys.
Ideally, we'd have used "i" for gcc, but it doesn't work in all cases
with -fPIC code. This is gcc-specific problem that doesn't exist in llvm.
Since clang does not have "jdd" simply always use "i" constraint for it.
Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
When we try to recover a PCI function using
echo 1 > /sys/bus/pci/devices/<id>/recover
or manually with
echo 1 > /sys/bus/pci/devices/<id>/remove
echo 0 > /sys/bus/pci/slots/<slot>/power
echo 1 > /sys/bus/pci/slots/<slot>/power
clp_disable_fn() / clp_enable_fn() call clp_set_pci_fn() to first
disable and then reenable the function.
When the function is already in the requested state we may be left with
an invalid function handle.
To get a new valid handle we do a clp_list_pci() call. For this we need
both the function ID and function handle in clp_set_pci_fn() so pass the
zdev and get both.
To simplify things also pull setting the refreshed function handle into
clp_set_pci_fn()
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
In order to avoid needless #ifdef CONFIG_COMPAT checks,
move the compat_ptr() definition to linux/compat.h
where it can be seen by any file regardless of the
architecture.
Only s390 needs a special definition, this can use the
self-#define trick we have elsewhere.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The following sequence triggers a kernel stack overflow on s390x:
mount -t tracefs tracefs /sys/kernel/tracing
cd /sys/kernel/tracing
echo function_graph > current_tracer
[crash]
This is because preempt_count_{add,sub} are in the list of traced
functions, which can be demonstrated by:
echo preempt_count_add >set_ftrace_filter
echo function_graph > current_tracer
[crash]
The stack overflow happens because get_tod_clock_monotonic() gets called
by ftrace but itself calls preempt_{disable,enable}(), which leads to a
endless recursion. Fix this by using preempt_{disable,enable}_notrace().
Fixes: 011620688a ("s390/time: ensure get_clock_monotonic() returns monotonic values")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
diag 0x44 is a voluntary undirected yield of a virtual CPU. This has
caused a lot of performance issues in the past.
There is only one caller left, and that one is only executed if diag
0x9c (directed yield) is not present. Given that all hypervisors
implement diag 0x9c anyway, remove the last diag 0x44 to avoid that
more callers will be added.
Worst case that could happen now, if diag 0x9c is not present, is that
a virtual CPU would loop a bit instead of giving its time slice up.
diag 0x44 statistics in debugfs are kept and will always be zero, so
that user space can tell that there are no calls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
ENOTSUP is just an internal kernel error and should never reach
userspace. The return value of the share function is not exported to
userspace, but to avoid giving bad examples let us use EOPNOTSUPP:
Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
In the x86 MM code we'd like to untangle various types of historic
header dependency spaghetti, but for this we'd need to pass to
the generic vmalloc code various vmalloc related defines that
customarily come via the <asm/page.h> low level arch header.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull more powerpc updates from Michael Ellerman:
"A few commits splitting the KASAN instrumented bitops header in three,
to match the split of the asm-generic bitops headers.
This is needed on powerpc because we use the generic bitops for the
non-atomic case only, whereas the existing KASAN instrumented bitops
assume all the underlying operations are provided by the arch as
arch_foo() versions.
Thanks to: Daniel Axtens & Christophe Leroy"
* tag 'powerpc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
docs/core-api: Remove possibly confusing sub-headings from Bit Operations
powerpc: support KASAN instrumentation of bitops
kasan: support instrumented bitops combined with generic bitops
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Warn if a host bridge has no NUMA info (Yunsheng Lin)
- Add PCI_STD_NUM_BARS for the number of standard BARs (Denis
Efremov)
Resource management:
- Fix boot-time Embedded Controller GPE storm caused by incorrect
resource assignment after ACPI Bus Check Notification (Mika
Westerberg)
- Protect pci_reassign_bridge_resources() against concurrent
addition/removal (Benjamin Herrenschmidt)
- Fix bridge dma_ranges resource list cleanup (Rob Herring)
- Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parameters to control
the MMIO and prefetchable MMIO window sizes of hotplug bridges
independently (Nicholas Johnson)
- Fix MMIO/MMIO_PREF window assignment that assigned more space than
desired (Nicholas Johnson)
- Only enforce bus numbers from bridge EA if the bridge has EA
devices downstream (Subbaraya Sundeep)
- Consolidate DT "dma-ranges" parsing and convert all host drivers to
use shared parsing (Rob Herring)
Error reporting:
- Restore AER capability after resume (Mayurkumar Patel)
- Add PoisonTLPBlocked AER counter (Rajat Jain)
- Use for_each_set_bit() to simplify AER code (Andy Shevchenko)
- Fix AER kernel-doc (Andy Shevchenko)
- Add "pcie_ports=dpc-native" parameter to allow native use of DPC
even if platform didn't grant control over AER (Olof Johansson)
Hotplug:
- Avoid returning prematurely from sysfs requests to enable or
disable a PCIe hotplug slot (Lukas Wunner)
- Don't disable interrupts twice when suspending hotplug ports (Mika
Westerberg)
- Fix deadlocks when PCIe ports are hot-removed while suspended (Mika
Westerberg)
Power management:
- Remove unnecessary ASPM locking (Bjorn Helgaas)
- Add support for disabling L1 PM Substates (Heiner Kallweit)
- Allow re-enabling Clock PM after it has been disabled (Heiner
Kallweit)
- Add sysfs attributes for controlling ASPM link states (Heiner
Kallweit)
- Remove CONFIG_PCIEASPM_DEBUG, including "link_state" and "clk_ctl"
sysfs files (Heiner Kallweit)
- Avoid AMD FCH XHCI USB PME# from D0 defect that prevents wakeup on
USB 2.0 or 1.1 connect events (Kai-Heng Feng)
- Move power state check out of pci_msi_supported() (Bjorn Helgaas)
- Fix incorrect MSI-X masking on resume and revert related nvme quirk
for Kingston NVME SSD running FW E8FK11.T (Jian-Hong Pan)
- Always return devices to D0 when thawing to fix hibernation with
drivers like mlx4 that used legacy power management (previously we
only did it for drivers with new power management ops) (Dexuan Cui)
- Clear PCIe PME Status even for legacy power management (Bjorn
Helgaas)
- Fix PCI PM documentation errors (Bjorn Helgaas)
- Use dev_printk() for more power management messages (Bjorn Helgaas)
- Apply D2 delay as milliseconds, not microseconds (Bjorn Helgaas)
- Convert xen-platform from legacy to generic power management (Bjorn
Helgaas)
- Removed unused .resume_early() and .suspend_late() legacy power
management hooks (Bjorn Helgaas)
- Rearrange power management code for clarity (Rafael J. Wysocki)
- Decode power states more clearly ("4" or "D4" really refers to
"D3cold") (Bjorn Helgaas)
- Notice when reading PM Control register returns an error (~0)
instead of interpreting it as being in D3hot (Bjorn Helgaas)
- Add missing link delays required by the PCIe spec (Mika Westerberg)
Virtualization:
- Move pci_prg_resp_pasid_required() to CONFIG_PCI_PRI (Bjorn
Helgaas)
- Allow VFs to use PRI (the PF PRI is shared by the VFs, but the code
previously didn't recognize that) (Kuppuswamy Sathyanarayanan)
- Allow VFs to use PASID (the PF PASID capability is shared by the
VFs, but the code previously didn't recognize that) (Kuppuswamy
Sathyanarayanan)
- Disconnect PF and VF ATS enablement, since ATS in PFs and
associated VFs can be enabled independently (Kuppuswamy
Sathyanarayanan)
- Cache PRI and PASID capability offsets (Kuppuswamy Sathyanarayanan)
- Cache the PRI PRG Response PASID Required bit (Bjorn Helgaas)
- Consolidate ATS declarations in linux/pci-ats.h (Krzysztof
Wilczynski)
- Remove unused PRI and PASID stubs (Bjorn Helgaas)
- Removed unnecessary EXPORT_SYMBOL_GPL() from ATS, PRI, and PASID
interfaces that are only used by built-in IOMMU drivers (Bjorn
Helgaas)
- Hide PRI and PASID state restoration functions used only inside the
PCI core (Bjorn Helgaas)
- Add a DMA alias quirk for the Intel VCA NTB (Slawomir Pawlowski)
- Serialize sysfs sriov_numvfs reads vs writes (Pierre Crégut)
- Update Cavium ACS quirk for ThunderX2 and ThunderX3 (George
Cherian)
- Fix the UPDCR register address in the Intel ACS quirk (Steffen
Liebergeld)
- Unify ACS quirk implementations (Bjorn Helgaas)
Amlogic Meson host bridge driver:
- Fix meson PERST# GPIO polarity problem (Remi Pommarel)
- Add DT bindings for Amlogic Meson G12A (Neil Armstrong)
- Fix meson clock names to match DT bindings (Neil Armstrong)
- Add meson support for Amlogic G12A SoC with separate shared PHY
(Neil Armstrong)
- Add meson extended PCIe PHY functions for Amlogic G12A USB3+PCIe
combo PHY (Neil Armstrong)
- Add arm64 DT for Amlogic G12A PCIe controller node (Neil Armstrong)
- Add commented-out description of VIM3 USB3/PCIe mux in arm64 DT
(Neil Armstrong)
Broadcom iProc host bridge driver:
- Invalidate iProc PAXB address mapping before programming it
(Abhishek Shah)
- Fix iproc-msi and mvebu __iomem annotations (Ben Dooks)
Cadence host bridge driver:
- Refactor Cadence PCIe host controller to use as a library for both
host and endpoint (Tom Joseph)
Freescale Layerscape host bridge driver:
- Add layerscape LS1028a support (Xiaowei Bao)
Intel VMD host bridge driver:
- Add VMD bus 224-255 restriction decode (Jon Derrick)
- Add VMD 8086:9A0B device ID (Jon Derrick)
- Remove Keith from VMD maintainer list (Keith Busch)
Marvell ARMADA 3700 / Aardvark host bridge driver:
- Use LTSSM state to build link training flag since Aardvark doesn't
implement the Link Training bit (Remi Pommarel)
- Delay before training Aardvark link in case PERST# was asserted
before the driver probe (Remi Pommarel)
- Fix Aardvark issues with Root Control reads and writes (Remi
Pommarel)
- Don't rely on jiffies in Aardvark config access path since
interrupts may be disabled (Remi Pommarel)
- Fix Aardvark big-endian support (Grzegorz Jaszczyk)
Marvell ARMADA 370 / XP host bridge driver:
- Make mvebu_pci_bridge_emul_ops static (Ben Dooks)
Microsoft Hyper-V host bridge driver:
- Add hibernation support for Hyper-V virtual PCI devices (Dexuan
Cui)
- Track Hyper-V pci_protocol_version per-hbus, not globally (Dexuan
Cui)
- Avoid kmemleak false positive on hv hbus buffer (Dexuan Cui)
Mobiveil host bridge driver:
- Change mobiveil csr_read()/write() function names that conflict
with riscv arch functions (Kefeng Wang)
NVIDIA Tegra host bridge driver:
- Fix Tegra CLKREQ dependency programming (Vidya Sagar)
Renesas R-Car host bridge driver:
- Remove unnecessary header include from rcar (Andrew Murray)
- Tighten register index checking for rcar inbound range programming
(Marek Vasut)
- Fix rcar inbound range alignment calculation to improve packing of
multiple entries (Marek Vasut)
- Update rcar MACCTLR setting to match documentation (Yoshihiro
Shimoda)
- Clear bit 0 of MACCTLR before PCIETCTLR.CFINIT per manual
(Yoshihiro Shimoda)
- Add Marek Vasut and Yoshihiro Shimoda as R-Car maintainers (Simon
Horman)
Rockchip host bridge driver:
- Make rockchip 0V9 and 1V8 power regulators non-optional (Robin
Murphy)
Socionext UniPhier host bridge driver:
- Set uniphier to host (RC) mode always (Kunihiko Hayashi)
Endpoint drivers:
- Fix endpoint driver sign extension problem when shifting page
number to phys_addr_t (Alan Mikhak)
Misc:
- Add NumaChip SPDX header (Krzysztof Wilczynski)
- Replace EXTRA_CFLAGS with ccflags-y (Krzysztof Wilczynski)
- Remove unused includes (Krzysztof Wilczynski)
- Removed unused sysfs attribute groups (Ben Dooks)
- Remove PTM and ASPM dependencies on PCIEPORTBUS (Bjorn Helgaas)
- Add PCIe Link Control 2 register field definitions to replace magic
numbers in AMDGPU and Radeon CIK/SI (Bjorn Helgaas)
- Fix incorrect Link Control 2 Transmit Margin usage in AMDGPU and
Radeon CIK/SI PCIe Gen3 link training (Bjorn Helgaas)
- Use pcie_capability_read_word() instead of pci_read_config_word()
in AMDGPU and Radeon CIK/SI (Frederick Lawler)
- Remove unused pci_irq_get_node() Greg Kroah-Hartman)
- Make asm/msi.h mandatory and simplify PCI_MSI_IRQ_DOMAIN Kconfig
(Palmer Dabbelt, Michal Simek)
- Read all 64 bits of Switchtec part_event_bitmap (Logan Gunthorpe)
- Fix erroneous intel-iommu dependency on CONFIG_AMD_IOMMU (Bjorn
Helgaas)
- Fix bridge emulation big-endian support (Grzegorz Jaszczyk)
- Fix dwc find_next_bit() usage (Niklas Cassel)
- Fix pcitest.c fd leak (Hewenliang)
- Fix typos and comments (Bjorn Helgaas)
- Fix Kconfig whitespace errors (Krzysztof Kozlowski)"
* tag 'pci-v5.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (160 commits)
PCI: Remove PCI_MSI_IRQ_DOMAIN architecture whitelist
asm-generic: Make msi.h a mandatory include/asm header
Revert "nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T"
PCI/MSI: Fix incorrect MSI-X masking on resume
PCI/MSI: Move power state check out of pci_msi_supported()
PCI/MSI: Remove unused pci_irq_get_node()
PCI: hv: Avoid a kmemleak false positive caused by the hbus buffer
PCI: hv: Change pci_protocol_version to per-hbus
PCI: hv: Add hibernation support
PCI: hv: Reorganize the code in preparation of hibernation
MAINTAINERS: Remove Keith from VMD maintainer
PCI/ASPM: Remove PCIEASPM_DEBUG Kconfig option and related code
PCI/ASPM: Add sysfs attributes for controlling ASPM link states
PCI: Fix indentation
drm/radeon: Prefer pcie_capability_read_word()
drm/radeon: Replace numbers with PCI_EXP_LNKCTL2 definitions
drm/radeon: Correct Transmit Margin masks
drm/amdgpu: Prefer pcie_capability_read_word()
PCI: uniphier: Set mode register to host mode
drm/amdgpu: Replace numbers with PCI_EXP_LNKCTL2 definitions
...
Pull more s390 updates from Vasily Gorbik:
- Make stack unwinder reliable and suitable for livepatching. Add
unwinder testing module.
- Fixes for CALL_ON_STACK helper used for stack switching.
- Fix unwinding from bpf code.
- Fix getcpu and remove compat support in vdso code.
- Fix address space control registers initialization.
- Save KASLR offset for early dumps.
- Handle new FILTERED_BY_HYPERVISOR reply code in crypto code.
- Minor perf code cleanup and potential memory leak fix.
- Add couple of error messages for corner cases during PCI device
creation.
* tag 's390-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (33 commits)
s390: remove compat vdso code
s390/livepatch: Implement reliable stack tracing for the consistency model
s390/unwind: add stack pointer alignment sanity checks
s390/unwind: filter out unreliable bogus %r14
s390/unwind: start unwinding from reliable state
s390/test_unwind: add program check context tests
s390/test_unwind: add irq context tests
s390/test_unwind: print verbose unwinding results
s390/test_unwind: add CALL_ON_STACK tests
s390: fix register clobbering in CALL_ON_STACK
s390/test_unwind: require that unwinding ended successfully
s390/unwind: add a test for the internal API
s390/unwind: always inline get_stack_pointer
s390/pci: add error message on device number limit
s390/pci: add error message for UID collision
s390/cpum_sf: Check for SDBT and SDB consistency
s390/cpum_sf: Use TEAR_REG macro consistantly
s390/cpum_sf: Remove unnecessary check for pending SDBs
s390/cpum_sf: Replace function name in debug statements
s390/kaslr: store KASLR offset for early dumps
...
A comment in arch/s390/include/asm/unwind.h says:
> If 'first_frame' is not zero unwind_start skips unwind frames until it
> reaches the specified stack pointer.
> The end of the unwinding is indicated with unwind_done, this can be true
> right after unwind_start, e.g. with first_frame!=0 that can not be found.
> unwind_next_frame skips to the next frame.
> Once the unwind is completed unwind_error() can be used to check if there
> has been a situation where the unwinder could not correctly understand
> the tasks call chain.
With this change backchain unwinder now comply with behaviour
described. As well as matches orc unwinder implementation. Now unwinder
starts from reliable state, i.e. __unwind_start own stack frame is
taken or stack frame generated by __switch_to (ksp) - both known to be
valid. In case of pt_regs %r15 is better match for pt_regs psw, than
sometimes random "sp" caller passed.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
CALL_ON_STACK defines and initializes register variables. Inline
assembly which follows might trigger compiler to generate memory access
for "stack" argument (e.g. in case of S390_lowcore.nodat_stack). This
memory access produces a function call under kasan with outline
instrumentation which clobbers registers.
Switch "stack" argument in CALL_ON_STACK helper to use memory reference
constraint and perform load instead.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
