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commit c9305b6c1f52060377c72aebe3a701389e9f3172 upstream.
Add proper alignment for .nospec_call_table and .nospec_return_table in
vmlinux.
[hca@linux.ibm.com]: The problem with the missing alignment of the nospec
tables exist since a long time, however only since commit e6ed91fd0768
("s390/alternatives: remove padding generation code") and with
CONFIG_RELOCATABLE=n the kernel may also crash at boot time.
The above named commit reduced the size of struct alt_instr by one byte,
so its new size is 11 bytes. Therefore depending on the number of cpu
alternatives the size of the __alt_instructions array maybe odd, which
again also causes that the addresses of the nospec tables will be odd.
If the address of __nospec_call_start is odd and the kernel is compiled
With CONFIG_RELOCATABLE=n the compiler may generate code that loads the
address of __nospec_call_start with a 'larl' instruction.
This will generate incorrect code since the 'larl' instruction only works
with even addresses. In result the members of the nospec tables will be
accessed with an off-by-one offset, which subsequently may lead to
addressing exceptions within __nospec_revert().
Fixes: f19fbd5ed642 ("s390: introduce execute-trampolines for branches")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/8719bf1ce4a72ebdeb575200290094e9ce047bcc.1661557333.git.jpoimboe@kernel.org
Cc: <stable@vger.kernel.org> # 4.16
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7c8d42fdf1a84b1a0dd60d6528309c8ec127e87c upstream.
The alignment check in prepare_hugepage_range() is wrong for 2 GB
hugepages, it only checks for 1 MB hugepage alignment.
This can result in kernel crash in __unmap_hugepage_range() at the
BUG_ON(start & ~huge_page_mask(h)) alignment check, for mappings
created with MAP_FIXED at unaligned address.
Fix this by correctly handling multiple hugepage sizes, similar to the
generic version of prepare_hugepage_range().
Fixes: d08de8e2d867 ("s390/mm: add support for 2GB hugepages")
Cc: <stable@vger.kernel.org> # 4.8+
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7b6670b03641ac308aaa6fa2e6f964ac993b5ea3 ]
When booting under KVM the following error messages are issued:
hypfs.7f5705: The hardware system does not support hypfs
hypfs.7a79f0: Initialization of hypfs failed with rc=-61
Demote the severity of first message from "error" to "info" and issue
the second message only in other error cases.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Link: https://lore.kernel.org/r/20220620094534.18967-1-jgross@suse.com
[arch/s390/hypfs/hypfs_diag.c changed description]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 41ac42f137080bc230b5882e3c88c392ab7f2d32 upstream.
For non-protection pXd_none() page faults in do_dat_exception(), we
call do_exception() with access == (VM_READ | VM_WRITE | VM_EXEC).
In do_exception(), vma->vm_flags is checked against that before
calling handle_mm_fault().
Since commit 92f842eac7ee3 ("[S390] store indication fault optimization"),
we call handle_mm_fault() with FAULT_FLAG_WRITE, when recognizing that
it was a write access. However, the vma flags check is still only
checking against (VM_READ | VM_WRITE | VM_EXEC), and therefore also
calling handle_mm_fault() with FAULT_FLAG_WRITE in cases where the vma
does not allow VM_WRITE.
Fix this by changing access check in do_exception() to VM_WRITE only,
when recognizing write access.
Link: https://lkml.kernel.org/r/20220811103435.188481-3-david@redhat.com
Fixes: 92f842eac7ee3 ("[S390] store indication fault optimization")
Cc: <stable@vger.kernel.org>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 13cccafe0edcd03bf1c841de8ab8a1c8e34f77d9 upstream.
The pointers for guarded storage and runtime instrumentation control
blocks are stored in the thread_struct of the associated task. These
pointers are initially copied on fork() via arch_dup_task_struct()
and then cleared via copy_thread() before fork() returns. If fork()
happens to fail after the initial task dup and before copy_thread(),
the newly allocated task and associated thread_struct memory are
freed via free_task() -> arch_release_task_struct(). This results in
a double free of the guarded storage and runtime info structs
because the fields in the failed task still refer to memory
associated with the source task.
This problem can manifest as a BUG_ON() in set_freepointer() (with
CONFIG_SLAB_FREELIST_HARDENED enabled) or KASAN splat (if enabled)
when running trinity syscall fuzz tests on s390x. To avoid this
problem, clear the associated pointer fields in
arch_dup_task_struct() immediately after the new task is copied.
Note that the RI flag is still cleared in copy_thread() because it
resides in thread stack memory and that is where stack info is
copied.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Fixes: 8d9047f8b967c ("s390/runtime instrumentation: simplify task exit handling")
Fixes: 7b83c6297d2fc ("s390/guarded storage: simplify task exit handling")
Cc: <stable@vger.kernel.org> # 4.15
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20220816155407.537372-1-bfoster@redhat.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0828c4a39be57768b8788e8cbd0d84683ea757e5 upstream.
commit e23a8020ce4e ("s390/kexec_file: Signature verification prototype")
adds support for KEXEC_SIG verification with keys from platform keyring
but the built-in keys and secondary keyring are not used.
Add support for the built-in keys and secondary keyring as x86 does.
Fixes: e23a8020ce4e ("s390/kexec_file: Signature verification prototype")
Cc: stable@vger.kernel.org
Cc: Philipp Rudo <prudo@linux.ibm.com>
Cc: kexec@lists.infradead.org
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: "Lee, Chun-Yi" <jlee@suse.com>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 918e75f77af7d2e049bb70469ec0a2c12782d96a upstream.
This patch slightly reworks the s390 arch_get_random_seed_{int,long}
implementation: Make sure the CPACF trng instruction is never
called in any interrupt context. This is done by adding an
additional condition in_task().
Justification:
There are some constrains to satisfy for the invocation of the
arch_get_random_seed_{int,long}() functions:
- They should provide good random data during kernel initialization.
- They should not be called in interrupt context as the TRNG
instruction is relatively heavy weight and may for example
make some network loads cause to timeout and buck.
However, it was not clear what kind of interrupt context is exactly
encountered during kernel init or network traffic eventually calling
arch_get_random_seed_long().
After some days of investigations it is clear that the s390
start_kernel function is not running in any interrupt context and
so the trng is called:
Jul 11 18:33:39 t35lp54 kernel: [<00000001064e90ca>] arch_get_random_seed_long.part.0+0x32/0x70
Jul 11 18:33:39 t35lp54 kernel: [<000000010715f246>] random_init+0xf6/0x238
Jul 11 18:33:39 t35lp54 kernel: [<000000010712545c>] start_kernel+0x4a4/0x628
Jul 11 18:33:39 t35lp54 kernel: [<000000010590402a>] startup_continue+0x2a/0x40
The condition in_task() is true and the CPACF trng provides random data
during kernel startup.
The network traffic however, is more difficult. A typical call stack
looks like this:
Jul 06 17:37:07 t35lp54 kernel: [<000000008b5600fc>] extract_entropy.constprop.0+0x23c/0x240
Jul 06 17:37:07 t35lp54 kernel: [<000000008b560136>] crng_reseed+0x36/0xd8
Jul 06 17:37:07 t35lp54 kernel: [<000000008b5604b8>] crng_make_state+0x78/0x340
Jul 06 17:37:07 t35lp54 kernel: [<000000008b5607e0>] _get_random_bytes+0x60/0xf8
Jul 06 17:37:07 t35lp54 kernel: [<000000008b56108a>] get_random_u32+0xda/0x248
Jul 06 17:37:07 t35lp54 kernel: [<000000008aefe7a8>] kfence_guarded_alloc+0x48/0x4b8
Jul 06 17:37:07 t35lp54 kernel: [<000000008aeff35e>] __kfence_alloc+0x18e/0x1b8
Jul 06 17:37:07 t35lp54 kernel: [<000000008aef7f10>] __kmalloc_node_track_caller+0x368/0x4d8
Jul 06 17:37:07 t35lp54 kernel: [<000000008b611eac>] kmalloc_reserve+0x44/0xa0
Jul 06 17:37:07 t35lp54 kernel: [<000000008b611f98>] __alloc_skb+0x90/0x178
Jul 06 17:37:07 t35lp54 kernel: [<000000008b6120dc>] __napi_alloc_skb+0x5c/0x118
Jul 06 17:37:07 t35lp54 kernel: [<000000008b8f06b4>] qeth_extract_skb+0x13c/0x680
Jul 06 17:37:07 t35lp54 kernel: [<000000008b8f6526>] qeth_poll+0x256/0x3f8
Jul 06 17:37:07 t35lp54 kernel: [<000000008b63d76e>] __napi_poll.constprop.0+0x46/0x2f8
Jul 06 17:37:07 t35lp54 kernel: [<000000008b63dbec>] net_rx_action+0x1cc/0x408
Jul 06 17:37:07 t35lp54 kernel: [<000000008b937302>] __do_softirq+0x132/0x6b0
Jul 06 17:37:07 t35lp54 kernel: [<000000008abf46ce>] __irq_exit_rcu+0x13e/0x170
Jul 06 17:37:07 t35lp54 kernel: [<000000008abf531a>] irq_exit_rcu+0x22/0x50
Jul 06 17:37:07 t35lp54 kernel: [<000000008b922506>] do_io_irq+0xe6/0x198
Jul 06 17:37:07 t35lp54 kernel: [<000000008b935826>] io_int_handler+0xd6/0x110
Jul 06 17:37:07 t35lp54 kernel: [<000000008b9358a6>] psw_idle_exit+0x0/0xa
Jul 06 17:37:07 t35lp54 kernel: ([<000000008ab9c59a>] arch_cpu_idle+0x52/0xe0)
Jul 06 17:37:07 t35lp54 kernel: [<000000008b933cfe>] default_idle_call+0x6e/0xd0
Jul 06 17:37:07 t35lp54 kernel: [<000000008ac59f4e>] do_idle+0xf6/0x1b0
Jul 06 17:37:07 t35lp54 kernel: [<000000008ac5a28e>] cpu_startup_entry+0x36/0x40
Jul 06 17:37:07 t35lp54 kernel: [<000000008abb0d90>] smp_start_secondary+0x148/0x158
Jul 06 17:37:07 t35lp54 kernel: [<000000008b935b9e>] restart_int_handler+0x6e/0x90
which confirms that the call is in softirq context. So in_task() covers exactly
the cases where we want to have CPACF trng called: not in nmi, not in hard irq,
not in soft irq but in normal task context and during kernel init.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Link: https://lore.kernel.org/r/20220713131721.257907-1-freude@linux.ibm.com
Fixes: e4f74400308c ("s390/archrandom: simplify back to earlier design and initialize earlier")
[agordeev@linux.ibm.com changed desc, added Fixes and Link, removed -stable]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 25deecb21c18ee29e3be8ac6177b2a9504c33d2d upstream.
Since commit 4c0f032d4963 ("s390/purgatory: Omit use of bin2c"),
s390 builds the purgatory without using bin2c.
Remove 'select BUILD_BIN2C' to avoid the unneeded build of bin2c.
Fixes: 4c0f032d4963 ("s390/purgatory: Omit use of bin2c")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20220613170902.1775211-1-masahiroy@kernel.org
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e4f74400308cb8abde5fdc9cad609c2aba32110c upstream.
s390x appears to present two RNG interfaces:
- a "TRNG" that gathers entropy using some hardware function; and
- a "DRBG" that takes in a seed and expands it.
Previously, the TRNG was wired up to arch_get_random_{long,int}(), but
it was observed that this was being called really frequently, resulting
in high overhead. So it was changed to be wired up to arch_get_random_
seed_{long,int}(), which was a reasonable decision. Later on, the DRBG
was then wired up to arch_get_random_{long,int}(), with a complicated
buffer filling thread, to control overhead and rate.
Fortunately, none of the performance issues matter much now. The RNG
always attempts to use arch_get_random_seed_{long,int}() first, which
means a complicated implementation of arch_get_random_{long,int}() isn't
really valuable or useful to have around. And it's only used when
reseeding, which means it won't hit the high throughput complications
that were faced before.
So this commit returns to an earlier design of just calling the TRNG in
arch_get_random_seed_{long,int}(), and returning false in arch_get_
random_{long,int}().
Part of what makes the simplification possible is that the RNG now seeds
itself using the TRNG at bootup. But this only works if the TRNG is
detected early in boot, before random_init() is called. So this commit
also causes that check to happen in setup_arch().
Cc: stable@vger.kernel.org
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Ingo Franzki <ifranzki@linux.ibm.com>
Cc: Juergen Christ <jchrist@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220610222023.378448-1-Jason@zx2c4.com
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3e35142ef99fe6b4fe5d834ad43ee13cca10a2dc upstream.
Since commit d1bcae833b32f1 ("ELF: Don't generate unused section
symbols") [1], binutils (v2.36+) started dropping section symbols that
it thought were unused. This isn't an issue in general, but with
kexec_file.c, gcc is placing kexec_arch_apply_relocations[_add] into a
separate .text.unlikely section and the section symbol ".text.unlikely"
is being dropped. Due to this, recordmcount is unable to find a non-weak
symbol in .text.unlikely to generate a relocation record against.
Address this by dropping the weak attribute from these functions.
Instead, follow the existing pattern of having architectures #define the
name of the function they want to override in their headers.
[1] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d1bcae833b32f1
[akpm@linux-foundation.org: arch/s390/include/asm/kexec.h needs linux/module.h]
Link: https://lkml.kernel.org/r/20220519091237.676736-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit be857b7f77d130dbbd47c91fc35198b040f35865 ]
Events CPU_CYCLES and INSTRUCTIONS can be submitted with two different
perf_event attribute::type values:
- PERF_TYPE_HARDWARE: when invoked via perf tool predefined events name
cycles or cpu-cycles or instructions.
- pmu->type: when invoked via perf tool event name cpu_cf/CPU_CYLCES/ or
cpu_cf/INSTRUCTIONS/. This invocation also selects the PMU to which
the event belongs.
Handle both type of invocations identical for events CPU_CYLCES and
INSTRUCTIONS. They address the same hardware.
The result is different when event modifier exclude_kernel is also set.
Invocation with event modifier for user space event counting fails.
Output before:
# perf stat -e cpum_cf/cpu_cycles/u -- true
Performance counter stats for 'true':
<not supported> cpum_cf/cpu_cycles/u
0.000761033 seconds time elapsed
0.000076000 seconds user
0.000725000 seconds sys
#
Output after:
# perf stat -e cpum_cf/cpu_cycles/u -- true
Performance counter stats for 'true':
349,613 cpum_cf/cpu_cycles/u
0.000844143 seconds time elapsed
0.000079000 seconds user
0.000800000 seconds sys
#
Fixes: 6a82e23f45fe ("s390/cpumf: Adjust registration of s390 PMU device drivers")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
[agordeev@linux.ibm.com corrected commit ID of Fixes commit]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3ae11dbcfac906a8c3a480e98660a823130dc16a upstream.
The switch to a keyed guest does not require a classic sske as the other
guest CPUs are not accessing the key before the switch is complete.
By using the NQ SSKE things are faster especially with multiple guests.
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Suggested-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220530092706.11637-3-borntraeger@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2e3df523256cb9836de8441e9c791a796759bb3c upstream.
S390x defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5e054c820f59bbb9714d5767f5f476581c309ca8 upstream.
These symbols are currently part of the generic archrandom.h
interface, but are currently unused and can be removed.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200110145422.49141-4-broonie@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6d5946274df1fff539a7eece458a43be733d1db8 ]
With large and many guest with storage keys it is possible to create
large latencies or stalls during initial key setting:
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 18-....: (2099 ticks this GP) idle=54e/1/0x4000000000000002 softirq=35598716/35598716 fqs=998
(t=2100 jiffies g=155867385 q=20879)
Task dump for CPU 18:
CPU 1/KVM R running task 0 1030947 256019 0x06000004
Call Trace:
sched_show_task
rcu_dump_cpu_stacks
rcu_sched_clock_irq
update_process_times
tick_sched_handle
tick_sched_timer
__hrtimer_run_queues
hrtimer_interrupt
do_IRQ
ext_int_handler
ptep_zap_key
The mmap lock is held during the page walking but since this is a
semaphore scheduling is still possible. Same for the kvm srcu.
To minimize overhead do this on every segment table entry or large page.
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220530092706.11637-2-borntraeger@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bd52cd5e23f134019b23f0c389db0f9a436e4576 ]
The argument of scatterwalk_unmap() is supposed to be the void* that was
returned by the previous scatterwalk_map() call.
The s390 AES-GCM implementation was instead passing the pointer to the
struct scatter_walk.
This doesn't actually break anything because scatterwalk_unmap() only uses
its argument under CONFIG_HIGHMEM and ARCH_HAS_FLUSH_ON_KUNMAP.
Fixes: bf7fa038707c ("s390/crypto: add s390 platform specific aes gcm support.")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517143047.3054498-1-jannh@google.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 63678eecec57fc51b778be3da35a397931287170 ]
gcc 12 does not (always) optimize away code that should only be generated
if parameters are constant and within in a certain range. This depends on
various obscure kernel config options, however in particular
PROFILE_ALL_BRANCHES can trigger this compile error:
In function ‘__atomic_add_const’,
inlined from ‘__preempt_count_add.part.0’ at ./arch/s390/include/asm/preempt.h:50:3:
./arch/s390/include/asm/atomic_ops.h:80:9: error: impossible constraint in ‘asm’
80 | asm volatile( \
| ^~~
Workaround this by simply disabling the optimization for
PROFILE_ALL_BRANCHES, since the kernel will be so slow, that this
optimization won't matter at all.
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8b202ee218395319aec1ef44f72043e1fbaccdd6 ]
gcc-12 shows a lot of array bound warnings on s390. This is caused
by the S390_lowcore macro which uses a hardcoded address of 0.
Wrapping that with absolute_pointer() works, but gcc no longer knows
that a 12 bit displacement is sufficient to access lowcore. So it
emits instructions like 'lghi %r1,0; l %rx,xxx(%r1)' instead of a
single load/store instruction. As s390 stores variables often
read/written in lowcore, this is considered problematic. Therefore
disable -Warray-bounds on s390 for gcc-12 for the time being, until
there is a better solution.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Link: https://lore.kernel.org/r/yt9dzgkelelc.fsf@linux.ibm.com
Link: https://lore.kernel.org/r/20220422134308.1613610-1-svens@linux.ibm.com
Link: https://lore.kernel.org/r/20220425121742.3222133-1-svens@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 663d34c8df98740f1e90241e78e456d00b3c6cad upstream.
Currently if z/VM guest is allowed to retrieve hypervisor performance
data globally for all guests (privilege class B) the query is formed in a
way to include all guests but the group name is left empty. This leads to
that z/VM guests which have access control group set not being included
in the results (even local vm).
Change the query group identifier from empty to "any" to retrieve
information about all guests from any groups (or without a group set).
Cc: stable@vger.kernel.org
Fixes: 31cb4bd31a48 ("[S390] Hypervisor filesystem (s390_hypfs) for z/VM")
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c2c224932fd0ee6854d6ebfc8d059c2bcad86606 upstream.
There is a race on concurrent 2KB-pgtables release paths when
both upper and lower halves of the containing parent page are
freed, one via page_table_free_rcu() + __tlb_remove_table(),
and the other via page_table_free(). The race might lead to a
corruption as result of remove of list item in page_table_free()
concurrently with __free_page() in __tlb_remove_table().
Let's assume first the lower and next the upper 2KB-pgtables are
freed from a page. Since both halves of the page are allocated
the tracking byte (bits 24-31 of the page _refcount) has value
of 0x03 initially:
CPU0 CPU1
---- ----
page_table_free_rcu() // lower half
{
// _refcount[31..24] == 0x03
...
atomic_xor_bits(&page->_refcount,
0x11U << (0 + 24));
// _refcount[31..24] <= 0x12
...
table = table | (1U << 0);
tlb_remove_table(tlb, table);
}
...
__tlb_remove_table()
{
// _refcount[31..24] == 0x12
mask = _table & 3;
// mask <= 0x01
...
page_table_free() // upper half
{
// _refcount[31..24] == 0x12
...
atomic_xor_bits(
&page->_refcount,
1U << (1 + 24));
// _refcount[31..24] <= 0x10
// mask <= 0x10
...
atomic_xor_bits(&page->_refcount,
mask << (4 + 24));
// _refcount[31..24] <= 0x00
// mask <= 0x00
...
if (mask != 0) // == false
break;
fallthrough;
...
if (mask & 3) // == false
...
else
__free_page(page); list_del(&page->lru);
^^^^^^^^^^^^^^^^^^ RACE! ^^^^^^^^^^^^^^^^^^^^^
} ...
}
The problem is page_table_free() releases the page as result of
lower nibble unset and __tlb_remove_table() observing zero too
early. With this update page_table_free() will use the similar
logic as page_table_free_rcu() + __tlb_remove_table(), and mark
the fragment as pending for removal in the upper nibble until
after the list_del().
In other words, the parent page is considered as unreferenced and
safe to release only when the lower nibble is cleared already and
unsetting a bit in upper nibble results in that nibble turned zero.
Cc: stable@vger.kernel.org
Suggested-by: Vlastimil Babka <vbabka@suse.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 812de04661c4daa7ac385c0dfd62594540538034 upstream.
With KVM_CAP_S390_USER_SIGP, there are only five Signal Processor
orders (CONDITIONAL EMERGENCY SIGNAL, EMERGENCY SIGNAL, EXTERNAL CALL,
SENSE, and SENSE RUNNING STATUS) which are intended for frequent use
and thus are processed in-kernel. The remainder are sent to userspace
with the KVM_CAP_S390_USER_SIGP capability. Of those, three orders
(RESTART, STOP, and STOP AND STORE STATUS) have the potential to
inject work back into the kernel, and thus are asynchronous.
Let's look for those pending IRQs when processing one of the in-kernel
SIGP orders, and return BUSY (CC2) if one is in process. This is in
agreement with the Principles of Operation, which states that only one
order can be "active" on a CPU at a time.
Cc: stable@vger.kernel.org
Suggested-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20211213210550.856213-2-farman@linux.ibm.com
[borntraeger@linux.ibm.com: add stable tag]
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 41967a37b8eedfee15b81406a9f3015be90d3980 ]
arch_kexec_apply_relocations_add currently ignores all errors returned
by arch_kexec_do_relocs. This means that every unknown relocation is
silently skipped causing unpredictable behavior while the relocated code
runs. Fix this by checking for errors and fail kexec_file_load if an
unknown relocation type is encountered.
The problem was found after gcc changed its behavior and used
R_390_PLT32DBL relocations for brasl instruction and relied on ld to
resolve the relocations in the final link in case direct calls are
possible. As the purgatory code is only linked partially (option -r)
ld didn't resolve the relocations leaving them for arch_kexec_do_relocs.
But arch_kexec_do_relocs doesn't know how to handle R_390_PLT32DBL
relocations so they were silently skipped. This ultimately caused an
endless loop in the purgatory as the brasl instructions kept branching
to itself.
Fixes: 71406883fd35 ("s390/kexec_file: Add kexec_file_load system call")
Reported-by: Tao Liu <ltao@redhat.com>
Signed-off-by: Philipp Rudo <prudo@redhat.com>
Link: https://lore.kernel.org/r/20211208130741.5821-3-prudo@redhat.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 52d04d408185b7aa47628d2339c28ec70074e0ae upstream.
When running without MIO support, with pci=nomio or for devices which
are not MIO-capable the zPCI subsystem generates pseudo-MMIO addresses
to allow access to PCI BARs via MMIO based Linux APIs even though the
platform uses function handles and BAR numbers.
This is done by stashing an index into our global IOMAP array which
contains the function handle in the 16 most significant bits of the
addresses returned by ioremap() always setting the most significant bit.
On the other hand the MIO addresses assigned by the platform for use,
while requiring special instructions, allow PCI access with virtually
mapped physical addresses. Now the problem is that these MIO addresses
and our own pseudo-MMIO addresses may overlap, while functionally this
would not be a problem by itself this overlap is detected by common code
as both address types are added as resources in the iomem_resource tree.
This leads to the overlapping resource claim of either the MIO capable
or non-MIO capable devices with being rejected.
Since PCI is tightly coupled to the use of the iomem_resource tree, see
for example the code for request_mem_region(), we can't reasonably get
rid of the overlap being detected by keeping our pseudo-MMIO addresses
out of the iomem_resource tree.
Instead let's move the range used by our own pseudo-MMIO addresses by
starting at (1UL << 62) and only using addresses below (1UL << 63) thus
avoiding the range currently used for MIO addresses.
Fixes: c7ff0e918a7c ("s390/pci: deal with devices that have no support for MIO instructions")
Cc: stable@vger.kernel.org # 5.3+
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5dbc4cb4667457b0c53bcd7bff11500b3c362975 ]
There is a difference in how architectures treat "mem=" option. For some
that is an amount of online memory, for s390 and x86 this is the limiting
max address. Some memblock api like memblock_enforce_memory_limit()
take limit argument and explicitly treat it as the size of online memory,
and use __find_max_addr to convert it to an actual max address. Current
s390 usage:
memblock_enforce_memory_limit(memblock_end_of_DRAM());
yields different results depending on presence of memory holes (offline
memory blocks in between online memory). If there are no memory holes
limit == max_addr in memblock_enforce_memory_limit() and it does trim
online memory and reserved memory regions. With memory holes present it
actually does nothing.
Since we already use memblock_remove() explicitly to trim online memory
regions to potential limit (think mem=, kdump, addressing limits, etc.)
drop the usage of memblock_enforce_memory_limit() altogether. Trimming
reserved regions should not be required, since we now use
memblock_set_current_limit() to limit allocations and any explicit memory
reservations above the limit is an actual problem we should not hide.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit fe3d10024073f06f04c74b9674bd71ccc1d787cf upstream.
We should not walk/touch page tables outside of VMA boundaries when
holding only the mmap sem in read mode. Evil user space can modify the
VMA layout just before this function runs and e.g., trigger races with
page table removal code since commit dd2283f2605e ("mm: mmap: zap pages
with read mmap_sem in munmap"). gfn_to_hva() will only translate using
KVM memory regions, but won't validate the VMA.
Further, we should not allocate page tables outside of VMA boundaries: if
evil user space decides to map hugetlbfs to these ranges, bad things will
happen because we suddenly have PTE or PMD page tables where we
shouldn't have them.
Similarly, we have to check if we suddenly find a hugetlbfs VMA, before
calling get_locked_pte().
Fixes: 2d42f9477320 ("s390/kvm: Add PGSTE manipulation functions")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20210909162248.14969-4-david@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 20c76e242e7025bd355619ba67beb243ba1a1e95 ]
kexec_file_add_ipl_report ignores that ipl_report_finish may fail and
can return an error pointer instead of a valid pointer.
Fix this and simplify by returning NULL in case of an error and let
the only caller handle this case.
Fixes: 99feaa717e55 ("s390/kexec_file: Create ipl report and pass to next kernel")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 85f517b29418158d3e6e90c3f0fc01b306d2f1a1 ]
If handle_sske cannot set the storage key, because there is no
page table entry or no present large page entry, it calls
fixup_user_fault.
However, currently, if the call succeeds, handle_sske returns
-EAGAIN, without having set the storage key.
Instead, retry by continue'ing the loop without incrementing the
address.
The same issue in handle_pfmf was fixed by
a11bdb1a6b78 ("KVM: s390: Fix pfmf and conditional skey emulation").
Fixes: bd096f644319 ("KVM: s390: Add skey emulation fault handling")
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20211022152648.26536-1-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b159f94c86b43cf7e73e654bc527255b1f4eafc4 ]
... otherwise we will try unlocking a spinlock that was never locked via a
garbage pointer.
At the time we reach this code path, we usually successfully looked up
a PGSTE already; however, evil user space could have manipulated the VMA
layout in the meantime and triggered removal of the page table.
Fixes: 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20210909162248.14969-3-david@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0e9ff65f455dfd0a8aea5e7843678ab6fe097e21 ]
Changing the deliverable mask in __airqs_kick_single_vcpu() is a bug. If
one idle vcpu can't take the interrupts we want to deliver, we should
look for another vcpu that can, instead of saying that we don't want
to deliver these interrupts by clearing the bits from the
deliverable_mask.
Fixes: 9f30f6216378 ("KVM: s390: add gib_alert_irq_handler()")
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20211019175401.3757927-3-pasic@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9b57e9d5010bbed7c0d9d445085840f7025e6f9a ]
The idea behind kicked mask is that we should not re-kick a vcpu that
is already in the "kick" process, i.e. that was kicked and is
is about to be dispatched if certain conditions are met.
The problem with the current implementation is, that it assumes the
kicked vcpu is going to enter SIE shortly. But under certain
circumstances, the vcpu we just kicked will be deemed non-runnable and
will remain in wait state. This can happen, if the interrupt(s) this
vcpu got kicked to deal with got already cleared (because the interrupts
got delivered to another vcpu). In this case kvm_arch_vcpu_runnable()
would return false, and the vcpu would remain in kvm_vcpu_block(),
but this time with its kicked_mask bit set. So next time around we
wouldn't kick the vcpu form __airqs_kick_single_vcpu(), but would assume
that we just kicked it.
Let us make sure the kicked_mask is cleared before we give up on
re-dispatching the vcpu.
Fixes: 9f30f6216378 ("KVM: s390: add gib_alert_irq_handler()")
Reported-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20211019175401.3757927-2-pasic@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8e0ab8e26b72a80e991c66a8abc16e6c856abe3d upstream.
Fix two problems found in the strrchr() implementation for s390
architectures: evaluate empty strings (return the string address instead of
NULL, if '\0' is passed as second argument); evaluate the first character
of non-empty strings (the current implementation stops at the second).
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Reported-by: Heiko Carstens <hca@linux.ibm.com> (incorrect behavior with empty strings)
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Link: https://lore.kernel.org/r/20211005120836.60630-1-roberto.sassu@huawei.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 686cb8b9f6b46787f035afe8fbd132a74e6b1bdd ]
Make sure to free jit_data through kfree() in the error path.
Fixes: 1c8f9b91c456 ("bpf: s390: add JIT support for multi-function programs")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit a8b92b8c1eac8d655a97b1e90f4d83c25d9b9a18 upstream.
We should not walk/touch page tables outside of VMA boundaries when
holding only the mmap sem in read mode. Evil user space can modify the
VMA layout just before this function runs and e.g., trigger races with
page table removal code since commit dd2283f2605e ("mm: mmap: zap pages
with read mmap_sem in munmap").
find_vma() does not check if the address is >= the VMA start address;
use vma_lookup() instead.
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Fixes: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap")
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e61dc9da0b7a0d91d57c2e20b5ea4fd2d4e7e53 upstream.
The JIT uses agfi for subtracting constants, but -(-0x80000000) cannot
be represented as a 32-bit signed binary integer. Fix by using algfi in
this particular case.
Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db7bee653859ef7179be933e7d1384644f795f26 upstream.
Currently the JIT completely removes things like `reg32 += 0`,
however, the BPF_ALU semantics requires the target register to be
zero-extended in such cases.
Fix by optimizing out only the arithmetic operation, but not the
subsequent zero-extension.
Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 93ebb6828723b8aef114415c4dc3518342f7dcad upstream.
Since commit 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for
swiotlb data bouncing") if code sets swiotlb_force it needs to do so
before the swiotlb is initialised. Otherwise
io_tlb_default_mem->force_bounce will not get set to true, and devices
that use (the default) swiotlb will not bounce despite switolb_force
having the value of SWIOTLB_FORCE.
Let us restore swiotlb functionality for PV by fulfilling this new
requirement.
This change addresses what turned out to be a fragility in
commit 64e1f0c531d1 ("s390/mm: force swiotlb for protected
virtualization"), which ain't exactly broken in its original context,
but could give us some more headache if people backport the broken
change and forget this fix.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Fixes: 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing")
Fixes: 64e1f0c531d1 ("s390/mm: force swiotlb for protected virtualization")
Cc: stable@vger.kernel.org #5.3+
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3322ba0d7bea1e24ae464418626f6a15b69533ab ]
Kernel support for the newer PCI mio instructions can be toggled off
with the pci=nomio command line option which needs to integrate with
common code PCI option parsing. However this option then toggles static
branches which can't be toggled yet in an early_param() call.
Thus commit 9964f396f1d0 ("s390: fix setting of mio addressing control")
moved toggling the static branches to the PCI init routine.
With this setup however we can't check for mio support outside the PCI
code during early boot, i.e. before switching the static branches, which
we need to be able to export this as an ELF HWCAP.
Improve on this by turning mio availability into a machine flag that
gets initially set based on CONFIG_PCI and the facility bit and gets
toggled off if pci=nomio is found during PCI option parsing allowing
simple access to this machine flag after early init.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5492886c14744d239e87f1b0b774b5a341e755cc ]
In case of a jump label print the real address of the piece of code
where a mismatch was detected. This is right before the system panics,
so there is nothing revealed.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit a3e03bc1368c1bc16e19b001fc96dc7430573cc8 upstream.
While in practice vcpu->vcpu_idx == vcpu->vcp_id is often true, it may
not always be, and we must not rely on this. Reason is that KVM decides
the vcpu_idx, userspace decides the vcpu_id, thus the two might not
match.
Currently kvm->arch.idle_mask is indexed by vcpu_id, which implies
that code like
for_each_set_bit(vcpu_id, kvm->arch.idle_mask, online_vcpus) {
vcpu = kvm_get_vcpu(kvm, vcpu_id);
do_stuff(vcpu);
}
is not legit. Reason is that kvm_get_vcpu expects an vcpu_idx, not an
vcpu_id. The trouble is, we do actually use kvm->arch.idle_mask like
this. To fix this problem we have two options. Either use
kvm_get_vcpu_by_id(vcpu_id), which would loop to find the right vcpu_id,
or switch to indexing via vcpu_idx. The latter is preferable for obvious
reasons.
Let us make switch from indexing kvm->arch.idle_mask by vcpu_id to
indexing it by vcpu_idx. To keep gisa_int.kicked_mask indexed by the
same index as idle_mask lets make the same change for it as well.
Fixes: 1ee0bc559dc3 ("KVM: s390: get rid of local_int array")
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Christian Bornträger <borntraeger@de.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: <stable@vger.kernel.org> # 3.15+
Link: https://lore.kernel.org/r/20210827125429.1912577-1-pasic@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f5e81d1117501546b7be050c5fbafa6efd2c722c upstream.
In case of JITs, each of the JIT backends compiles the BPF nospec instruction
/either/ to a machine instruction which emits a speculation barrier /or/ to
/no/ machine instruction in case the underlying architecture is not affected
by Speculative Store Bypass or has different mitigations in place already.
This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence'
instruction for mitigation. In case of arm64, we rely on the firmware mitigation
as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled,
it works for all of the kernel code with no need to provide any additional
instructions here (hence only comment in arm64 JIT). Other archs can follow
as needed. The BPF nospec instruction is specifically targeting Spectre v4
since i) we don't use a serialization barrier for the Spectre v1 case, and
ii) mitigation instructions for v1 and v4 might be different on some archs.
The BPF nospec is required for a future commit, where the BPF verifier does
annotate intermediate BPF programs with speculation barriers.
Co-developed-by: Piotr Krysiuk <piotras@gmail.com>
Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[OP: - adjusted context for 5.4
- apply riscv changes to /arch/riscv/net/bpf_jit_comp.c]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9372a82892c2caa6bccab9a4081166fa769699f8 ]
Currently allocation and registration of s390dbf debug areas are tied
together. As a result, a debug area cannot be unregistered and
re-registered while any process has an associated debugfs file open.
Fix this by splitting alloc/release from register/unregister.
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ddd63c85ef67ea9ea7282ad35eafb6568047126e ]
It is currently possible to initialize a large PMD page when
the address is not aligned on page boundary.
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 463f36c76fa4ec015c640ff63ccf52e7527abee0 upstream.
The DMA code section of the decompressor must be compiled with expolines
if Spectre V2 mitigation has been enabled for the decompressed kernel.
This is required because although the decompressor's image contains
the DMA code section, it is handed over to the decompressed kernel for use.
Because the DMA code is already slow w/o expolines, use expolines always
regardless whether the decompressed kernel is using them or not. This
simplifies the DMA code by dropping the conditional compilation of
expolines.
Fixes: bf72630130c2 ("s390: use proper expoline sections for .dma code")
Cc: <stable@vger.kernel.org> # 5.2
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 91091656252f5d6d8c476e0c92776ce9fae7b445 ]
Currently array jit->seen_reg[r1] is being accessed before the range
checking of index r1. The range changing on r1 should be performed
first since it will avoid any potential out-of-range accesses on the
array seen_reg[] and also it is more optimal to perform checks on r1
before fetching data from the array. Fix this by swapping the order
of the checks before the array access.
Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20210715125712.24690-1-colin.king@canonical.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 41d71fe59cce41237f24f3b7bdc1b414069a34ed ]
The existing CALL_ON_STACK() macro allows for subtle bugs:
- There is no type checking of the function that is being called. That
is: missing or too many arguments do not cause any compile error or
warning. The same is true if the return type of the called function
changes. This can lead to quite random bugs.
- Sign and zero extension of arguments is missing. Given that the s390
C ABI requires that the caller of a function performs proper sign
and zero extension this can also lead to subtle bugs.
- If arguments to the CALL_ON_STACK() macros contain functions calls
register corruption can happen due to register asm constructs being
used.
Therefore introduce a new call_on_stack() macro which is supposed to
fix all these problems.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit da9057576785aaab52e706e76c0475c85b77ec14 ]
The tprot() inline asm temporarily changes the program check new psw
to redirect a potential program check on the diag instruction.
Restoring of the program check new psw is done in C code behind the
inline asm.
This can be problematic, especially if the function is inlined, since
the compiler can reorder instructions in such a way that a different
instruction, which may result in a program check, might be executed
before the program check new psw has been restored.
To avoid such a scenario move restoring into the inline asm. For
consistency reasons move also saving of the original program check new
psw into the inline asm.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 86807f348f418a84970eebb8f9912a7eea16b497 ]
The __diag260() inline asm temporarily changes the program check new
psw to redirect a potential program check on the diag instruction.
Restoring of the program check new psw is done in C code behind the
inline asm.
This can be problematic, especially if the function is inlined, since
the compiler can reorder instructions in such a way that a different
instruction, which may result in a program check, might be executed
before the program check new psw has been restored.
To avoid such a scenario move restoring into the inline asm. For
consistency reasons move also saving of the original program check new
psw into the inline asm.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
