- 18 Aug, 2021 1 commit
-
-
Vineeth Vijayan authored
This patch introduces a new rescan sys-interface for channel-subsystem. The rescan interface allows the user to invoke an evaluation of all subchannels defined in the I/O configuration. The new rescan interface can be found at /sys/devices/css0/rescan and can be triggered by, echo > /sys/devices/css0/rescan Writing to this interface triggers subchannel evaluation. The write request completes only after scan-related work has completed This user-invoked subchannel evaluation allows manual recovery in error situations such as: - restart of device discovery after resolution of temporary device error - inconsistent OS view of subchannel state due to missing state-change interrupts (CRWs) Signed-off-by:
Vineeth Vijayan <vneethv@linux.ibm.com> Reviewed-by:
Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by:
Vasily Gorbik <gor@linux.ibm.com>
-
- 05 Aug, 2021 4 commits
-
-
Heiko Carstens authored
The dma section name is confusing, since the code which resides within that section has nothing to do with direct memory access. Instead the limitation is that the code has to run in 31 bit addressing mode, and therefore has to reside below 2GB. So the name was chosen since ZONE_DMA is the same region. To reduce confusion rename the section to amode31, which hopefully describes better what this is about. Note: this will also change vmcoreinfo strings - SDMA=... gets renamed to SAMODE31=... - EDMA=... gets renamed to EAMODE31=... Acked-by:
Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by:
Heiko Carstens <hca@linux.ibm.com>
-
Heiko Carstens authored
Fix virtual vs physical address confusion (which currently are the same). Reviewed-by:
Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by:
-
Sebastian Andrzej Siewior authored
The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Signed-off-by:
Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20210803141621.780504-6-bigeasy@linutronix.deSigned-off-by:
-
Sebastian Andrzej Siewior authored
The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Signed-off-by:
-
- 03 Aug, 2021 2 commits
-
-
Ilya Leoshkevich authored
s390 allows hotpatching the mask of a conditional jump instruction. Make use of this feature in order to avoid the expensive stop_machine() call. The new trampolines are split in 3 stages: - A first stage is a 6-byte relative conditional long branch located at each function's entry point. Its offset always points to the second stage for the corresponding function, and its mask is either all 0s (ftrace off) or all 1s (ftrace on). The code for flipping the mask is borrowed from ftrace_{enable,disable}_ftrace_graph_caller. After flipping, ftrace_arch_code_modify_post_process() syncs with all the other CPUs by sending SIGPs. - Second stages for vmlinux are stored in a separate part of the .text section reserved by the linker script, and in dynamically allocated memory for modules. This prevents the icache pollution. The total size of second stages is about 1.5% of that of the kernel image. Putting second stages in the .bss section is possible and decreases the size of the non-compressed vmlinux, but splits the kernel 1:1 mapping, which is a bad tradeoff. Each second stage contains a call to the third stage, a pointer to the part of the intercepted function right after the first stage, and a pointer to an interceptor function (e.g. ftrace_caller). Second stages are 8-byte aligned for the future direct calls implementation. - There are only two copies of the third stage: in the .text section for vmlinux and in dynamically allocated memory for modules. It can be an expoline, which is relatively large, so inlining it into each second stage is prohibitively expensive. As a result of this organization, phoronix-test-suite with ftrace off does not show any performance degradation. Suggested-by:Sven Schnelle <svens@linux.ibm.com> Suggested-by:
Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/20210728212546.128248-3-iii@linux.ibm.comSigned-off-by:
-
Ilya Leoshkevich authored
Implementing live patching on s390 requires each function's prologue to contain a very special kind of nop, which gcc and clang don't generate. However, the current code assumes that if CC_USING_NOP_MCOUNT is defined, then whatever the compiler generates is good enough. Move the CC_USING_NOP_MCOUNT check into the new ftrace_need_init_nop() macro, that the architectures can override. An alternative solution is to disable using -mnop-mcount in the Makefile, however, this makes the build logic (even) more complicated and forces the arch-specific code to deal with the useless __fentry__ symbol. Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20210728212546.128248-2-iii@linux.ibm.comSigned-off-by:
-
- 30 Jul, 2021 8 commits
-
-
Masahiro Yamada authored
Currently, the install target in arch/s390/Makefile descends into arch/s390/boot/Makefile to invoke the shell script, but there is no good reason to do so. arch/s390/Makefile can run the shell script directly. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20210729142338.446002-1-masahiroy@kernel.orgSigned-off-by:
-
Ilya Leoshkevich authored
s390x GCC and SystemZ Clang have ThreadSanitizer support now [1] [2], so enable KCSAN for s390. [1] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ea22954e7c58 [2] https://reviews.llvm.org/D105629Signed-off-by:
-
Heiko Carstens authored
cycles_t has a different type across architectures: unsigned int, unsinged long, or unsigned long long. Depending on architecture this will generate this warning: kernel/kcsan/debugfs.c: In function ‘microbenchmark’: ./include/linux/kern_levels.h:5:25: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘cycles_t’ {aka ‘long unsigned int’} [-Wformat=] To avoid this simply change the type of cycle to u64 in microbenchmark(), since u64 is of type unsigned long long for all architectures. Acked-by:Marco Elver <elver@google.com> Link: https://lore.kernel.org/r/20210729142811.1309391-1-hca@linux.ibm.comSigned-off-by:
-
Sven Schnelle authored
Signed-off-by:
-
Sven Schnelle authored
Signed-off-by:
-
Sven Schnelle authored
s390 only reports the page address during a translation fault. To make the kfence unit tests pass, add a function that might be implemented by architectures to mask out address bits. Signed-off-by:
-
Heiko Carstens authored
Implement set_memory_4k() which will split any present large or huge mapping in the given range to a 4k mapping. Link: https://lore.kernel.org/r/20210728190254.3921642-2-hca@linux.ibm.comSigned-off-by:
-
Marco Elver authored
x86's <asm/tlbflush.h> only declares non-module accessible functions (such as flush_tlb_one_kernel) if !MODULE. In preparation of including <asm/kfence.h> from the KFENCE test module, only define the helpers if !MODULE to avoid breaking the build with CONFIG_KFENCE_KUNIT_TEST=m. Signed-off-by:
-
- 27 Jul, 2021 25 commits
-
-
Heiko Carstens authored
After all the changes to delay.c there are many includes which are not needed anymore. Get rid of them. Signed-off-by: -
Heiko Carstens authored
sparse warning: CHECK arch/s390/boot/startup.c arch/s390/boot/startup.c:283:39: error: arithmetics on pointers to functions Signed-off-by: -
Ilya Leoshkevich authored
struct brace should be on the same line. Signed-off-by:
-
Heiko Carstens authored
Commit 7f16d7e7 ("s390: show virtualization support in /proc/cpuinfo") introduced special handling for sie capability, saying this should not be exposed via hwcaps, without giving a reason. However this leads to an inconsistent /proc/cpuinfo features line where all features except the sie capability are also present in hwcaps. I really don't see a reason to not add that to hwcaps - it might be quite pointless, but at least this way it is possible to get rid of some special handling. Signed-off-by:
-
Heiko Carstens authored
Remove the not so obvious "(elf_hwcap & (1UL << 2)" which only checks if stfle is available. This used to be required for old code before test_facility() was introduced. test_facility() will do the right thing, regardless if stfle is available or not. Signed-off-by: -
Heiko Carstens authored
Remove a leftover from the common 31/64 bit code. z/Architecture mode is now always active, there is no need to check. Signed-off-by: -
Heiko Carstens authored
Use a consistent coding style within setup_hwcaps() and remove obvious and outdated comments. Signed-off-by: -
Heiko Carstens authored
The first six hwcap bits are initialized in a rather odd way: an array contains the stfl(e) bits which need to be set, so that the corresponding bit position (= array index) within hwcaps are set. Better open code it like it is done for all other bits, making it obvious which bit is set when. Signed-off-by: -
Heiko Carstens authored
setup_hwcaps() is a quite large function. Make it smaller by moving the elf platform setup code into an independent setup function. Signed-off-by: -
Heiko Carstens authored
Move setup_hwcaps() to processor.c for two reasons: - make setup.c a bit smaller - have allmost all of the hwcap code in one file Signed-off-by: -
Heiko Carstens authored
Add BUILD_BUG_ON() sanity checks to make sure the hwcap string array contains a string for each hwcap. Signed-off-by: -
Heiko Carstens authored
Use named initializers to make it obvious which hwcap string array element belongs to which hwcap. Signed-off-by: -
Heiko Carstens authored
Introduce HWCAP bit numbers, making it easier to tell at which bit number we currently are. Also use these bits with the BIT macro to define the real HWCAP masks. Signed-off-by: -
Heiko Carstens authored
Remove s390 part of all HWCAP defines, just to make them shorter and easier to handle. The namespace is anyway per architecture. This is similar to what arm64 has. Signed-off-by: -
Niklas Schnelle authored
In order to support the use of enhanced PCI instructions in both kernel- and userspace we need both hardware support and proper setup in the kernel. The latter can be toggled off with the pci=nomio command line option. Thus availability of this feature in userspace depends on all of kernel configuration (CONFIG_PCI), hardware support and the current kernel command line and can thus not rely solely on a facility bit. Instead let's introduce a new ELF hardware capability bit HWCAP_S390_PCI_MIO to tell userspace whether these PCI instructions can be used. Reviewed-by:
Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by:
-
Niklas Schnelle authored
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 9964f396 ("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 authored
Add more instructions to the kernel disassembler. Signed-off-by: -
Heiko Carstens authored
Add hardware capability bits and feature tags to /proc/cpuinfo for NNPA and Vector-Packed-Decimal-Enhancement Facility 2. Signed-off-by: -
Julian Wiedmann authored
These macros haven't seen any use in a long time. Also note that the queue_irqs_*() ones wouldn't even compile anymore. Signed-off-by:
Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by:
Benjamin Block <bblock@linux.ibm.com> Signed-off-by:
-
Julian Wiedmann authored
Now that all drivers use qdio_inspect_queue() and qdio's internal queue tasklets are gone, the driver-specified queue handlers are only called for async error reporting (eg. for an error condition in the QEBSM code). So take a moment to clean up the Output Queue handlers (they are _always_ called with qdio_error != 0), and clarify which error types can be reported through what interface. As Benjamin already suggested a while ago, we should turn these into distinct enums at some point. Signed-off-by:
-
Julian Wiedmann authored
get_outbound_buffer_frontier() is only reached via qdio_inspect_queue(), and there we already call qdio_siga_sync_q() unconditionally. Signed-off-by:
-
Julian Wiedmann authored
Both qdio drivers have moved away from using qdio's internal tasklet and timer mechanisms for Output Queues. Rip out all the leftovers. Signed-off-by:
-
Julian Wiedmann authored
If qdio_cancel_ccw() times out (or is interrupted) before the interrupt for the {halt,clear} action arrives, report this back to the caller as an error. Signed-off-by: -
Julian Wiedmann authored
If the ESTABLISH ccw fails (ie. the qdio_irq is set to QDIO_IRQ_STATE_ERR), we don't need to call qdio_shutdown() for rolling back our earlier actions. All the needed logic is already available in qdio_establish()'s error chain, and using it means we don't have to temporarily drop the setup_mutex either. This makes qdio_shutdown() a purely external function, that should only be called by the driver if an earlier qdio_establish() succeeded. Signed-off-by:
-
Julian Wiedmann authored
When the ESTABLISH ccw does not complete within the specified timeout, try our best to cancel the ccw program that is still active on the device. Otherwise the IO subsystem might be accessing it even after the driver eg. called qdio_free(). Fixes: 779e6e1c ("[S390] qdio: new qdio driver.") Signed-off-by:
-
