For system damage machine checks or machine checks due to invalid PSW
fields the system will be stopped. In order to get an oops message out
before killing the system the machine check handler branches to
.Lmcck_panic, switches to the panic stack and then does the usual
machine check handling.
The switch to the panic stack is incomplete, the stack pointer in %r15
is replaced, but the pt_regs pointer in %r11 is not. The result is
a program check which will kill the system in a slightly different way.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When converting from bootmem to memblock I missed a subtle difference:
the memblock_alloc() functions return uninitialized memory, while the
memblock_virt_alloc() functions return zeroed memory.
This led to quite random early boot crashes.
Therefore use the correct version everywhere now.
Hopefully.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When re-adding crash kernel memory within setup_resources() the
function memblock_add() is used. That function will add memory by
default to node "MAX_NUMNODES" instead of node 0, like the memory
detection code does. In case of !NUMA this will trigger this warning
when the kernel generates the vmemmap:
Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead
WARNING: CPU: 0 PID: 0 at mm/memblock.c:1261 memblock_virt_alloc_internal+0x76/0x220
CPU: 0 PID: 0 Comm: swapper Not tainted 4.9.0-rc6 #16
Call Trace:
[<0000000000d0b2e8>] memblock_virt_alloc_try_nid+0x88/0xc8
[<000000000083c8ea>] __earlyonly_bootmem_alloc.constprop.1+0x42/0x50
[<000000000083e7f4>] vmemmap_populate+0x1ac/0x1e0
[<0000000000840136>] sparse_mem_map_populate+0x46/0x68
[<0000000000d0c59c>] sparse_init+0x184/0x238
[<0000000000cf45f6>] paging_init+0xbe/0xf8
[<0000000000cf1d4a>] setup_arch+0xa02/0xae0
[<0000000000ced75a>] start_kernel+0x72/0x450
[<0000000000100020>] _stext+0x20/0x80
If NUMA is selected numa_setup_memory() will fix the node assignments
before the vmemmap will be populated; so this warning will only appear
if NUMA is not selected.
To fix this simply use memblock_add_node() and re-add crash kernel
memory explicitly to node 0.
Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Fixes: 4e042af463 ("s390/kexec: fix crash on resize of reserved memory")
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of all remaining alloc_bootmem calls and use memblock_alloc
instead everywhere. This way we get rid of the inconsistent mixture
of alloc_bootmem and memblock_alloc usages.
Two of the alloc_bootmem_low calls within arch/s390/kernel/setup.c are
replaced with memblock_alloc calls that don't enforce that the
allocated memory is below 2GB. This restriction was never necessary.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The LAST_BREAK macro in entry.S uses a different instruction sequence
for CONFIG_MARCH_Z900 builds. The branch target offset to skip the
store of the last breaking event address needs to take the different
length of the code block into account.
Fixes: f8fc82b471 ("s390: move sys_call_table and last_break from thread_info to thread_struct")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In order to make the cma infrastructure usable we need to add a small
architecture backend which calls dma_contiguous_reserve.
Otherwise we would end up with the cma allocator enabled, but no pool
where memory can be allocated from.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the psw_bits macro and simplify the code. The generated code is
also better since it doesn't contain any conditional branches anymore.
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We have the s390 specific THREAD_ORDER define and the THREAD_SIZE_ORDER
define which is also used in common code. Both have exactly the same
semantics. Therefore get rid of THREAD_ORDER and always use
THREAD_SIZE_ORDER instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The TOD clock offset injected by an STP sync check can be negative.
If the resulting total tod_steering_delta gets negative the kernel
will panic.
Change the type of tod_steering_delta to a signed type.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 75c7b6f3f6 ("s390/time: steer clocksource on STP sync events")
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move the last two architecture specific fields from the thread_info
structure to the thread_struct. All that is left in thread_info is
the flags field.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The user_timer and system_timer fields are used for the per-thread
cputime accounting code. The access to these values is simpler if
they are moved to the thread_struct as the task_thread_info(tsk)
indirection is not needed anymore.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The system_call field in thread_info structure is used by the signal
code to store the number of the current system call while the debugger
interacts with its inferior. A better location for the system_call
field is with the other debugger related information in the
thread_struct.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This is the s390 variant of commit 15f4eae70d ("x86: Move
thread_info into task_struct").
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert s390 to use a field in the struct lowcore for the CPU
preemption count. It is a bit cheaper to access a lowcore field
compared to a thread_info variable and it removes the depencency
on a task related structure.
bloat-o-meter on the vmlinux image for the default configuration
(CONFIG_PREEMPT_NONE=y) reports a small reduction in text size:
add/remove: 0/0 grow/shrink: 18/578 up/down: 228/-5448 (-5220)
A larger improvement is achieved with the default configuration
but with CONFIG_PREEMPT=y and CONFIG_DEBUG_PREEMPT=n:
add/remove: 2/6 grow/shrink: 59/4477 up/down: 1618/-228762 (-227144)
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The Makefile currently controlling compilation of this code is obj-y
meaning that it currently is not being built as a module by anyone.
Lets remove the couple traces of modular infrastructure use, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We replace module.h with init.h and export.h since the file does
export some symbols.
Cc: linux-s390@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On STP sync events the TOD clock will jump in time, either forward or
backward. The TOD clocksource claims to be continuous but in case of
an STP sync with a negative offset it is not.
Subtract the offset injected by the STP sync check from the result of
the TOD clocksource to make it continuous again. Add code to drift the
offset towards zero with a fixed rate, steering 1 second in ~9 hours.
Suggested-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The last_update_clock time stamp in the lowcore should be adjusted by
the TOD clock delta that is created by the clock synchronization.
Otherwise the calculation of the steal time will be incorrect.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Merge clock_sync_cpu into stp_sync_clock and split out the update
of the global and per-CPU clock fields into clock_sync_global
and clock_sync_local.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use pr_cont instead of printk calls also within show_stack and
die in order to avoid extra line breaks.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With commit ef6000b4c6 ("Disable the __builtin_return_address()
warning globally after all)" the kernel does not warn at all again if
__builtin_return_address(n) is called with n > 0.
Besides the fact that this was a false warning on s390 anyway, due to
the always present backchain, we can now revert commit 5606330627
("s390/dumpstack: implement and use return_address()") again, to
simplify the code again.
After all I shouldn't have had return_address() implememted at all to
workaround this issue. So get rid of this again.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Before merging all different stack tracers the call traces printed had
an indicator if an entry can be considered reliable or not.
Unreliable entries were put in braces, reliable not. Currently all
lines contain these extra braces.
This patch restores the old behaviour by adding an extra "reliable"
parameter to the callback functions. Only show_trace makes currently
use of it.
Before:
[ 0.804751] Call Trace:
[ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[ 0.804756] ([<0000000000161d64>] create_worker+0x174/0x1c0)
After:
[ 0.804751] Call Trace:
[ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[ 0.804756] [<0000000000161d64>] create_worker+0x174/0x1c0
Fixes: 758d39ebd3 ("s390/dumpstack: merge all four stack tracers")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull kbuild updates from Michal Marek:
- EXPORT_SYMBOL for asm source by Al Viro.
This does bring a regression, because genksyms no longer generates
checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
working on a patch to fix this.
Plus, we are talking about functions like strcpy(), which rarely
change prototypes.
- Fixes for PPC fallout of the above by Stephen Rothwell and Nick
Piggin
- fixdep speedup by Alexey Dobriyan.
- preparatory work by Nick Piggin to allow architectures to build with
-ffunction-sections, -fdata-sections and --gc-sections
- CONFIG_THIN_ARCHIVES support by Stephen Rothwell
- fix for filenames with colons in the initramfs source by me.
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
initramfs: Escape colons in depfile
ppc: there is no clear_pages to export
powerpc/64: whitelist unresolved modversions CRCs
kbuild: -ffunction-sections fix for archs with conflicting sections
kbuild: add arch specific post-link Makefile
kbuild: allow archs to select link dead code/data elimination
kbuild: allow architectures to use thin archives instead of ld -r
kbuild: Regenerate genksyms lexer
kbuild: genksyms fix for typeof handling
fixdep: faster CONFIG_ search
ia64: move exports to definitions
sparc32: debride memcpy.S a bit
[sparc] unify 32bit and 64bit string.h
sparc: move exports to definitions
ppc: move exports to definitions
arm: move exports to definitions
s390: move exports to definitions
m68k: move exports to definitions
alpha: move exports to actual definitions
x86: move exports to actual definitions
...
Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D
array.
If number of gids is <= 32, memory allocation is more or less tolerable
(140/148 bytes). But if it is not, code allocates full page (!)
regardless and, what's even more fun, doesn't reuse small 32-entry
array.
2D array means dependent shifts, loads and LEAs without possibility to
optimize them (gid is never known at compile time).
All of the above is unnecessary. Switch to the usual
trailing-zero-len-array scheme. Memory is allocated with
kmalloc/vmalloc() and only as much as needed. Accesses become simpler
(LEA 8(gi,idx,4) or even without displacement).
Maximum number of gids is 65536 which translates to 256KB+8 bytes. I
think kernel can handle such allocation.
On my usual desktop system with whole 9 (nine) aux groups, struct
group_info shrinks from 148 bytes to 44 bytes, yay!
Nice side effects:
- "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing,
- fix little mess in net/ipv4/ping.c
should have been using GROUP_AT macro but this point becomes moot,
- aux group allocation is persistent and should be accounted as such.
Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Vasily Kulikov <segoon@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative. Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".
We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.
This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.
Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All architectures:
Move `make kvmconfig` stubs from x86; use 64 bits for debugfs stats.
ARM:
Important fixes for not using an in-kernel irqchip; handle SError
exceptions and present them to guests if appropriate; proxying of GICV
access at EL2 if guest mappings are unsafe; GICv3 on AArch32 on ARMv8;
preparations for GICv3 save/restore, including ABI docs; cleanups and
a bit of optimizations.
MIPS:
A couple of fixes in preparation for supporting MIPS EVA host kernels;
MIPS SMP host & TLB invalidation fixes.
PPC:
Fix the bug which caused guests to falsely report lockups; other minor
fixes; a small optimization.
s390:
Lazy enablement of runtime instrumentation; up to 255 CPUs for nested
guests; rework of machine check deliver; cleanups and fixes.
x86:
IOMMU part of AMD's AVIC for vmexit-less interrupt delivery; Hyper-V
TSC page; per-vcpu tsc_offset in debugfs; accelerated INS/OUTS in
nVMX; cleanups and fixes.
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Merge tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
"All architectures:
- move `make kvmconfig` stubs from x86
- use 64 bits for debugfs stats
ARM:
- Important fixes for not using an in-kernel irqchip
- handle SError exceptions and present them to guests if appropriate
- proxying of GICV access at EL2 if guest mappings are unsafe
- GICv3 on AArch32 on ARMv8
- preparations for GICv3 save/restore, including ABI docs
- cleanups and a bit of optimizations
MIPS:
- A couple of fixes in preparation for supporting MIPS EVA host
kernels
- MIPS SMP host & TLB invalidation fixes
PPC:
- Fix the bug which caused guests to falsely report lockups
- other minor fixes
- a small optimization
s390:
- Lazy enablement of runtime instrumentation
- up to 255 CPUs for nested guests
- rework of machine check deliver
- cleanups and fixes
x86:
- IOMMU part of AMD's AVIC for vmexit-less interrupt delivery
- Hyper-V TSC page
- per-vcpu tsc_offset in debugfs
- accelerated INS/OUTS in nVMX
- cleanups and fixes"
* tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (140 commits)
KVM: MIPS: Drop dubious EntryHi optimisation
KVM: MIPS: Invalidate TLB by regenerating ASIDs
KVM: MIPS: Split kernel/user ASID regeneration
KVM: MIPS: Drop other CPU ASIDs on guest MMU changes
KVM: arm/arm64: vgic: Don't flush/sync without a working vgic
KVM: arm64: Require in-kernel irqchip for PMU support
KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL
KVM: PPC: Book3S: Remove duplicate setting of the B field in tlbie
KVM: PPC: BookE: Fix a sanity check
KVM: PPC: Book3S HV: Take out virtual core piggybacking code
KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
ARM: gic-v3: Work around definition of gic_write_bpr1
KVM: nVMX: Fix the NMI IDT-vectoring handling
KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive
KVM: nVMX: Fix reload apic access page warning
kvmconfig: add virtio-gpu to config fragment
config: move x86 kvm_guest.config to a common location
arm64: KVM: Remove duplicating init code for setting VMID
ARM: KVM: Support vgic-v3
...
Pull s390 updates from Martin Schwidefsky:
"The new features and main improvements in this merge for v4.9
- Support for the UBSAN sanitizer
- Set HAVE_EFFICIENT_UNALIGNED_ACCESS, it improves the code in some
places
- Improvements for the in-kernel fpu code, in particular the overhead
for multiple consecutive in kernel fpu users is recuded
- Add a SIMD implementation for the RAID6 gen and xor operations
- Add RAID6 recovery based on the XC instruction
- The PCI DMA flush logic has been improved to increase the speed of
the map / unmap operations
- The time synchronization code has seen some updates
And bug fixes all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
s390/con3270: fix insufficient space padding
s390/con3270: fix use of uninitialised data
MAINTAINERS: update DASD maintainer
s390/cio: fix accidental interrupt enabling during resume
s390/dasd: add missing \n to end of dev_err messages
s390/config: Enable config options for Docker
s390/dasd: make query host access interruptible
s390/dasd: fix panic during offline processing
s390/dasd: fix hanging offline processing
s390/pci_dma: improve lazy flush for unmap
s390/pci_dma: split dma_update_trans
s390/pci_dma: improve map_sg
s390/pci_dma: simplify dma address calculation
s390/pci_dma: remove dma address range check
iommu/s390: simplify registration of I/O address translation parameters
s390: migrate exception table users off module.h and onto extable.h
s390: export header for CLP ioctl
s390/vmur: fix irq pointer dereference in int handler
s390/dasd: add missing KOBJ_CHANGE event for unformatted devices
s390: enable UBSAN
...
These files were only including module.h for exception table
related functions. We've now separated that content out into its
own file "extable.h" so now move over to that and avoid all the
extra header content in module.h that we don't really need to compile
these files.
The additions of uaccess.h are to deal with implict includes like:
arch/s390/kernel/traps.c: In function 'do_report_trap':
arch/s390/kernel/traps.c:56:4: error: implicit declaration of function 'extable_fixup' [-Werror=implicit-function-declaration]
arch/s390/kernel/traps.c: In function 'illegal_op':
arch/s390/kernel/traps.c:173:3: error: implicit declaration of function 'get_user' [-Werror=implicit-function-declaration]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This enables UBSAN for s390. We have to disable the null sanitizer
as s390 code does access memory via a null pointer (the prefix page).
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The combo of list_empty() check and return list_first_entry()
can be replaced with list_first_entry_or_null().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Let's also write the external damage code already provided by
struct kvm_s390_mchk_info.
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The machine check handler will do one of two things if the floating-point
control, a floating point register or a vector register can not be
revalidated:
1) if the PSW indicates user mode the process is terminated
2) if the PSW indicates kernel mode the system is stopped
To unconditionally stop the system for 2) is incorrect.
There are three possible outcomes if the floating-point control, a
floating point register or a vector registers can not be revalidated:
1) The kernel is inside a kernel_fpu_begin/kernel_fpu_end block and
needs the register. The system is stopped.
2) No active kernel_fpu_begin/kernel_fpu_end block and the CIF_CPU bit
is not set. The user space process needs the register and is killed.
3) No active kernel_fpu_begin/kernel_fpu_end block and the CIF_FPU bit
is set. Neither the kernel nor the user space process needs the
lost register. Just revalidate it and continue.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of nested user of the FPU or vector registers in the kernel
the current code uses the mask of the FPU/vector registers of the
previous contexts to decide which registers to save and restore.
E.g. if the previous context used KERNEL_VXR_V0V7 and the next
context wants to use KERNEL_VXR_V24V31 the first 8 vector registers
are stored to the FPU state structure. But this is not necessary
as the next context does not use these registers.
Rework the FPU/vector register save and restore code. The new code
does a few things differently:
1) A lowcore field is used instead of a per-cpu variable.
2) The kernel_fpu_end function now has two parameters just like
kernel_fpu_begin. The register flags are required by both
functions to save / restore the minimal register set.
3) The inline functions kernel_fpu_begin/kernel_fpu_end now do the
update of the register masks. If the user space FPU registers
have already been stored neither save_fpu_regs nor the
__kernel_fpu_begin/__kernel_fpu_end functions have to be called
for the first context. In this case kernel_fpu_begin adds 7
instructions and kernel_fpu_end adds 4 instructions.
3) The inline assemblies in __kernel_fpu_begin / __kernel_fpu_end
to save / restore the vector registers are simplified a bit.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The increment might not be atomic and we're not holding the
timekeeper_lock. Therefore we might lose an update to count, resulting in
VDSO being trapped in a loop. As other archs also simply update the
values and count doesn't seem to have an impact on reloading of these
values in VDSO code, let's just remove the update of tb_update_count.
Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
By leaving fixup_cc unset, only the clock comparator of the cpu actually
doing the sync is fixed up until now.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There are still some etr leftovers and wrong comments, let's clean that up.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The way we call do_adjtimex() today is broken. It has 0 effect, as
ADJ_OFFSET_SINGLESHOT (0x0001) in the kernel maps to !ADJ_ADJTIME
(in contrast to user space where it maps to ADJ_OFFSET_SINGLESHOT |
ADJ_ADJTIME - 0x8001). !ADJ_ADJTIME will silently ignore all adjustments
without STA_PLL being active. We could switch to ADJ_ADJTIME or turn
STA_PLL on, but still we would run into some problems:
- Even when switching to nanoseconds, we lose accuracy.
- Successive calls to do_adjtimex() will simply overwrite any leftovers
from the previous call (if not fully handled)
- Anything that NTP does using the sysctl heavily interferes with our
use.
- !ADJ_ADJTIME will silently round stuff > or < than 0.5 seconds
Reusing do_adjtimex() here just feels wrong. The whole STP synchronization
works right now *somehow* only, as do_adjtimex() does nothing and our
TOD clock jumps in time, although it shouldn't. This is especially bad
as the clock could jump backwards in time. We will have to find another
way to fix this up.
As leap seconds are also not properly handled yet, let's just get rid of
all this complex logic altogether and use the correct clock_delta for
fixing up the clock comparator and keeping the sched_clock monotonic.
This change should have 0 effect on the current STP mechanism. Once we
know how to best handle sync events and leap second updates, we'll start
with a fresh implementation.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit 97f2645f35 ("tree-wide: replace config_enabled() with
IS_ENABLED()") mostly killed config_enabled(), but some new users have
appeared for v4.8-rc1. They are all used for a boolean option, so can
be replaced with IS_ENABLED() safely.
Link: http://lkml.kernel.org/r/1471970749-24867-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Storing this value will help prevent unwinders from getting out of sync
with the function graph tracer ret_stack. Now instead of needing a
stateful iterator, they can compare the return address pointer to find
the right ret_stack entry.
Note that an array of 50 ftrace_ret_stack structs is allocated for every
task. So when an arch implements this, it will add either 200 or 400
bytes of memory usage per task (depending on whether it's a 32-bit or
64-bit platform).
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a95cfcc39e8f26b89a430c56926af0bb217bc0a1.1471607358.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The way the decompressor is hooked into the start-up code is rather
subtle, with a mix of multiply-defined symbols and hardcoded address
literals. Add some comments at the junction points to clarify how it
works.
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
VGIC implementation.
- s390: support for trapping software breakpoints, nested virtualization
(vSIE), the STHYI opcode, initial extensions for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
preliminary to this and the upcoming support for hardware virtualization
extensions.
- x86: support for execute-only mappings in nested EPT; reduced vmexit
latency for TSC deadline timer (by about 30%) on Intel hosts; support for
more than 255 vCPUs.
- PPC: bugfixes.
The ugly bit is the conflicts. A couple of them are simple conflicts due
to 4.7 fixes, but most of them are with other trees. There was definitely
too much reliance on Acked-by here. Some conflicts are for KVM patches
where _I_ gave my Acked-by, but the worst are for this pull request's
patches that touch files outside arch/*/kvm. KVM submaintainers should
probably learn to synchronize better with arch maintainers, with the
latter providing topic branches whenever possible instead of Acked-by.
This is what we do with arch/x86. And I should learn to refuse pull
requests when linux-next sends scary signals, even if that means that
submaintainers have to rebase their branches.
Anyhow, here's the list:
- arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
by the nvdimm tree. This tree adds handle_preemption_timer and
EXIT_REASON_PREEMPTION_TIMER at the same place. In general all mentions
of pcommit have to go.
There is also a conflict between a stable fix and this patch, where the
stable fix removed the vmx_create_pml_buffer function and its call.
- virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
This tree adds kvm_io_bus_get_dev at the same place.
- virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
file was completely removed for 4.8.
- include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
this is a change that should have gone in through the irqchip tree and
pulled by kvm-arm. I think I would have rejected this kvm-arm pull
request. The KVM version is the right one, except that it lacks
GITS_BASER_PAGES_SHIFT.
- arch/powerpc: what a mess. For the idle_book3s.S conflict, the KVM
tree is the right one; everything else is trivial. In this case I am
not quite sure what went wrong. The commit that is causing the mess
(fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
and arch/powerpc/kvm/. It's large, but at 396 insertions/5 deletions
I guessed that it wasn't really possible to split it and that the 5
deletions wouldn't conflict. That wasn't the case.
- arch/s390: also messy. First is hypfs_diag.c where the KVM tree
moved some code and the s390 tree patched it. You have to reapply the
relevant part of commits 6c22c98637, plus all of e030c1125e, to
arch/s390/kernel/diag.c. Or pick the linux-next conflict
resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
Second, there is a conflict in gmap.c between a stable fix and 4.8.
The KVM version here is the correct one.
I have pushed my resolution at refs/heads/merge-20160802 (commit
3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
- ARM: GICv3 ITS emulation and various fixes. Removal of the
old VGIC implementation.
- s390: support for trapping software breakpoints, nested
virtualization (vSIE), the STHYI opcode, initial extensions
for CPU model support.
- MIPS: support for MIPS64 hosts (32-bit guests only) and lots
of cleanups, preliminary to this and the upcoming support for
hardware virtualization extensions.
- x86: support for execute-only mappings in nested EPT; reduced
vmexit latency for TSC deadline timer (by about 30%) on Intel
hosts; support for more than 255 vCPUs.
- PPC: bugfixes.
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
KVM: PPC: Introduce KVM_CAP_PPC_HTM
MIPS: Select HAVE_KVM for MIPS64_R{2,6}
MIPS: KVM: Reset CP0_PageMask during host TLB flush
MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
MIPS: KVM: Sign extend MFC0/RDHWR results
MIPS: KVM: Fix 64-bit big endian dynamic translation
MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
MIPS: KVM: Use 64-bit CP0_EBase when appropriate
MIPS: KVM: Set CP0_Status.KX on MIPS64
MIPS: KVM: Make entry code MIPS64 friendly
MIPS: KVM: Use kmap instead of CKSEG0ADDR()
MIPS: KVM: Use virt_to_phys() to get commpage PFN
MIPS: Fix definition of KSEGX() for 64-bit
KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
kvm: x86: nVMX: maintain internal copy of current VMCS
KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
KVM: arm64: vgic-its: Simplify MAPI error handling
KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
...
This fixes the same issue Steven already fixed for x86
in following commit:
237d28db03 ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing
It fixes the crash, that happens when function graph tracing
and jprobes are used simultaneously. Please refer to above
commit for details.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Fix this one when gcov is enabled:
arch/s390/kernel/als.o:(.data+0x118): undefined reference to `__gcov_merge_add'
arch/s390/kernel/als.o: In function `_GLOBAL__sub_I_65535_0_verify_facilities':
(.text.startup+0x8): undefined reference to `__gcov_init'
Please merge with "s390/als: convert architecture level set code to C".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the kernel needs more facilities to run than the machine provides
it is running on, print the facility bit numbers which are missing.
This allows to easily tell what went wrong and if simply the machine
does not provide a required facility or if either the kernel or the
hypervisor may have a bug.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If we have a facility mismatch the kernel only emits a warning that
the processor is not recent enough and stops operating. This doesn't
give us a lot of an idea of what actually went wrong.
As a first step print the machine type in addition.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is no reason to have this code in assembly language. Therefore
convert it to C.
Note that this code needs special treatment: it is called very early
and one of the side effects is that e.g. the bss section is not
cleared. Therefore the preferred way for static variables is to put
them on the stack which has a size of 16KB.
There is no functional change with this patch.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The early sclp code may be called before the bss section is
cleared. Therefore move all variables to the data section.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
