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2020-03-23s390/ipl: add support to control memory clearing for FCP and CCW re-IPLGerald Schaefer1-7/+66
Re-IPL for both CCW and FCP is currently done by using diag 308 with the "Load Clear" subcode, which means that all memory will be cleared. This can increase re-IPL duration considerably on very large machines. For CCW devices, there is also a "Load Normal" subcode that was only used for dump kernels so far. For FCP devices, a similar "Load Normal" subcode was introduced with z14. The "Load Normal" diag 308 subcode allows to re-IPL without clearing memory. This patch adds a new "clear" sysfs attribute to /sys/firmware/reipl for both the ccw and fcp subdirectories, which can be set to either "0" or "1" to disable or enable re-IPL with memory clearing. The default value is "0", which disables memory clearing. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-06s390/protvirt: avoid memory sharing for diag 308 set/storeVasily Gorbik1-9/+0
This reverts commit db9492cef45e ("s390/protvirt: add memory sharing for diag 308 set/store") which due to ultravisor implementation change is not needed after all. Fixes: db9492cef45e ("s390/protvirt: add memory sharing for diag 308 set/store") Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-07-11s390/ipl: Fix detection of has_secure attributePhilipp Rudo1-6/+1
Use the correct bit for detection of the machine capability associated with the has_secure attribute. It is expected that the underlying platform (including hypervisors) unsets the bit when they don't provide secure ipl for their guests. Fixes: c9896acc7851 ("s390/ipl: Provide has_secure sysfs attribute") Cc: stable@vger.kernel.org # 5.2 Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-05-02s390: simplify disabled_waitMartin Schwidefsky1-2/+2
The disabled_wait() function uses its argument as the PSW address when it stops the CPU with a wait PSW that is disabled for interrupts. The different callers sometimes use a specific number like 0xdeadbeef to indicate a specific failure, the early boot code uses 0 and some other calls sites use __builtin_return_address(0). At the time a dump is created the current PSW and the registers of a CPU are written to lowcore to make them avaiable to the dump analysis tool. For a CPU stopped with disabled_wait the PSW and the registers do not really make sense together, the PSW address does not point to the function the registers belong to. Simplify disabled_wait() by using _THIS_IP_ for the PSW address and drop the argument to the function. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29s390/kernel: introduce .dma sectionsGerald Schaefer1-1/+1
With a relocatable kernel that could reside at any place in memory, code and data that has to stay below 2 GB needs special handling. This patch introduces .dma sections for such text, data and ex_table. The sections will be part of the decompressor kernel, so they will not be relocated and stay below 2 GB. Their location is passed over to the decompressed / relocated kernel via the .boot.preserved.data section. The duald and aste for control register setup also need to stay below 2 GB, so move the setup code from arch/s390/kernel/head64.S to arch/s390/boot/head.S. The duct and linkage_stack could reside above 2 GB, but their content has to be preserved for the decompresed kernel, so they are also moved into the .dma section. The start and end address of the .dma sections is added to vmcoreinfo, for crash support, to help debugging in case the kernel crashed there. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29s390/ipl: Provide has_secure sysfs attributePhilipp Rudo1-0/+17
Provide an interface for userspace so it can find out if a machine is capeable of doing secure boot. The interface is, for example, needed for zipl so it can find out which file format it can/should write to disk. Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26s390/ipl: add helper functions to create an IPL reportMartin Schwidefsky1-0/+134
PR: Adjusted to the use in kexec_file later. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26s390/ipl: read IPL report at early bootMartin Schwidefsky1-0/+19
Read the IPL Report block provided by secure-boot, add the entries of the certificate list to the system key ring and print the list of components. PR: Adjust to Vasilys bootdata_preserved patch set. Preserve ipl_cert_list for later use in kexec_file. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26s390/ipl: provide uapi header for list directed IPLMartin Schwidefsky1-41/+39
The IPL parameter block is used as an interface between Linux and the machine to query and change the boot device and boot options. To be able to create IPL parameter block in user space and pass it as segment to kexec provide an uapi header with proper structure definitions for the block. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26s390/ipl: make ipl_info less confusingMartin Schwidefsky1-56/+54
The ipl_info union in struct ipl_parameter_block has the same name as the struct ipl_info. This does not help while reading the code and the union in struct ipl_parameter_block does not need to be named. Drop the name from the union. Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10s390/protvirt: add memory sharing for diag 308 set/storeVasily Gorbik1-0/+9
Add sharing of ipl parameter block for diag 308 set/store calls to allow kvm access in protected virtualization environment. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10s390: move ipl block to .boot.preserved.data sectionVasily Gorbik1-13/+2
.boot.preserved.data is a better fit for ipl block than .boot.data which is discarded after init. Reusing .boot.preserved.data allows to simplify code a little bit and avoid copying data from .boot.data to persistent variables. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09s390/kasan: reipl and kexec supportVasily Gorbik1-0/+2
Some functions from both arch/s390/kernel/ipl.c and arch/s390/kernel/machine_kexec.c are called without DAT enabled (or with and without DAT enabled code paths). There is no easy way to partially disable kasan for those files without a substantial rework. Disable kasan for both files for now. To avoid disabling kasan for arch/s390/kernel/diag.c DAT flag is enabled in diag308 call. pcpu_delegate which disables DAT is marked with __no_sanitize_address to disable instrumentation for that one function. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09s390: move ipl block and cmd line handling to early boot phaseVasily Gorbik1-106/+11
To distinguish zfcpdump case and to be able to parse some of the kernel command line arguments early (e.g. mem=) ipl block retrieval and command line construction code is moved to the early boot phase. "memory_end" is set up correctly respecting "mem=" and hsa_size in case of the zfcpdump. arch/s390/boot/string.c is introduced to provide string handling and command line parsing functions to early boot phase code for the compressed kernel image case. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: remove reipl_method and dump_methodVasily Gorbik1-46/+11
reipl_method and dump_method have been used in addition to reipl_type and dump_type, because a single reipl_type could be achieved with multiple reipl_method (same for dump_type/method). After dropping non-diag308_set based reipl methods, there is a single method per reipl_type/dump_type and reipl_method and dump_method could be simply removed. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: correct kdump reipl block checksum calculationVasily Gorbik1-6/+5
s390 kdump reipl implementation relies on os_info kernel structure residing in old memory being dumped. os_info contains reipl block, which is used (if valid) by the kdump kernel for reipl parameters. The problem is that the reipl block and its checksum inside os_info is updated only when /sys/firmware/reipl/reipl_type is written. This sets an offset of a reipl block for "reipl_type" and re-calculates reipl block checksum. Any further alteration of values under /sys/firmware/reipl/{reipl_type}/ without subsequent write to /sys/firmware/reipl/reipl_type lead to incorrect os_info reipl block checksum. In such a case kdump kernel ignores it and reboots using default logic. To fix this, os_info reipl block update is moved right before kdump execution. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390: assume diag308 set always worksVasily Gorbik1-198/+11
diag308 set has been available for many machine generations, and alternative reipl code paths has not been exercised and seems to be broken without noticing for a while now. So, cleaning up all obsolete reipl methods except currently used ones, assuming that diag308 set always works. Also removing not longer needed reset callbacks. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: avoid adding scpdata to cmdline during ftp/dvd bootVasily Gorbik1-1/+1
Add missing ipl parmblock validity check to append_ipl_scpdata. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: correct ipl parmblock valid checksVasily Gorbik1-6/+4
In some cases diag308_set_works used to be misused as "we have valid ipl parmblock", which is not the case when diag308 set works, but there is no ipl parmblock (diag308 store returns DIAG308_RC_NOCONFIG). Such checks are adjusted to reuse ipl_block_valid instead of diag308_set_works. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: rely on diag308 store to get ipl infoVasily Gorbik1-38/+15
For both ccw and fcp boot retrieve ipl info from ipl block received via diag308 store. Old scsi ipl parm block handling and cio_get_iplinfo are removed. Ipl type is deducted from ipl block (if valid). Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: move ipl_flags to ipl.cVasily Gorbik1-1/+9
ipl_flags and corresponding enum are not used outside of ipl.c and will be reworked in later commits. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: get rid of ipl_ssid and ipl_devnoVasily Gorbik1-9/+8
ipl_ssid and ipl_devno used to be used during ccw boot when diag308 store was not available. Reuse ipl_block to store those values. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: unite diag308 and scsi boot ipl blocksVasily Gorbik1-25/+25
Ipl parm blocks received via "diag308 store" and during scsi boot at IPL_PARMBLOCK_ORIGIN are merged into the "ipl_block". Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10s390/ipl: ensure loadparm valid flag is setVasily Gorbik1-0/+1
When loadparm is set in reipl parm block, the kernel should also set DIAG308_FLAGS_LP_VALID flag. This fixes loadparm ignoring during z/VM fcp -> ccw reipl and kvm direct boot -> ccw reipl. Cc: <stable@vger.kernel.org> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-05s390: add options to change branch prediction behaviour for the kernelMartin Schwidefsky1-0/+1
Add the PPA instruction to the system entry and exit path to switch the kernel to a different branch prediction behaviour. The instructions are added via CPU alternatives and can be disabled with the "nospec" or the "nobp=0" kernel parameter. If the default behaviour selected with CONFIG_KERNEL_NOBP is set to "n" then the "nobp=1" parameter can be used to enable the changed kernel branch prediction. Acked-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-01-23s390/ipl: avoid usage of __section(.data)Vasily Gorbik1-8/+4
bss section is cleared before ipl.c code is called or global variables are used nowadays. Remove stale comment and __section(.data) from few global variables. Also removes static/global variables initialization to 0. Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-24s390: kernel: add SPDX identifiers to the remaining filesGreg Kroah-Hartman1-0/+1
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-08s390: remove named saved segment supportHeiko Carstens1-36/+0
Remove the support to create a z/VM named saved segment (NSS). This feature is not supported since quite a while in favour of jump labels, function tracing and (now) CPU alternatives. All of these features require to write to the kernel text section which is not possible if the kernel is contained within an NSS. Given that memory savings are minimal if kernel images are shared and in addition updates of shared images are painful, the NSS feature can be removed. Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-06-14s390/ipl: revert Load Normal semantics for LPAR CCW-type re-IPLHeiko Carstens1-6/+1
This reverts the two commits 7afbeb6df2aa ("s390/ipl: always use load normal for CCW-type re-IPL") 0f7451ff3ab8 ("s390/ipl: use load normal for LPAR re-ipl") The two commits did not take into account that behavior of standby memory changes fundamentally if the re-IPL method is changed from Load Clear to Load Normal. In case of the old re-IPL clear method all memory that was initially in standby state will be put into standby state again within the re-IPL process. Or in other words: memory that was brought online before a re-IPL will be offline again after a reboot. Given that we use different re-IPL methods depending on the hypervisor and CCW-type vs SCSI re-IPL it is not easy to tell in advance when and why memory will stay online or will be offline after a re-IPL. This does also have other side effects, since memory that is online from the beginning will be in ZONE_NORMAL by default vs ZONE_MOVABLE for memory that is offline. Therefore, before the change, a user could online and offline memory easily since standby memory was always in ZONE_NORMAL. After the change, and a re-IPL, this depended on which memory parts were online before the re-IPL. From a usability point of view the current behavior is more than suboptimal. Therefore revert these changes until we have a better solution and get back to a consistent behavior. The bad thing about this is that the time required for a re-IPL will be significantly increased for configurations with several 100GB or 1TB of memory. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-02s390/ipl: always use load normal for CCW-type re-IPLHeiko Carstens1-0/+2
commit 14890678687c ("s390/ipl: use load normal for LPAR re-ipl") missed to convert one code path to use load normal semantics for re-IPL. Convert the missing code path as well. Fixes: 14890678687c ("s390/ipl: use load normal for LPAR re-ipl") Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-17s390: kernel: Audit and remove any unnecessary uses of module.hPaul Gortmaker1-1/+2
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each change instance for the presence of either and replace as needed. Build testing revealed some implicit header usage that was fixed up accordingly. 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>
2017-02-08s390/sclp: make early sclp code readableHeiko Carstens1-1/+1
This patch - unifies the old sclp early code and the sclp early printk code, so they can use common functions - makes sure all sclp early functions and variables have the same "sclp_early" prefix - converts the sclp early printk code into readable code by using existing data structures instead of hard coded magic arrays - splits the early sclp code into two files: sclp_early.c and sclp_early_core.c. The core file contains everything that is required by the kernel decompressor and may not call functions not contained within the core file. Otherwise the result would be a link error. - changes interrupt handling to be completely synchronous. The old early sclp code had a small window which allowed to receive several interrupts instead of exactly the single expected interrupt. This did hide a subtle potential bug, which is fixed with this large rework. - contains a couple of small cleanups. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-01-16s390: proper type casts for csum_partial invocationsHeiko Carstens1-1/+2
Keep sparse and other static code checkers from emitting warnings like: arch/s390/kernel/ipl.c:1549:14: warning: incorrect type in assignment (different base types) arch/s390/kernel/ipl.c:1549:14: expected unsigned int [unsigned] csum arch/s390/kernel/ipl.c:1549:14: got restricted __wsum All usages in s390 code are ok. Therefore add proper casts. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-12s390: fix initrd corruptions with gcov/kcov instrumented kernelsHeiko Carstens1-6/+1
The early C code within arch/s390/kernel/early.c saves ipl parameters before the bss section is cleared. When doing that it jumps to code that is potentially gcov/kcov instrumented. That code in turn will corrupt an initrd that potentially may reside in the not yet ready to be used bss section. Instead of excluding more and more code from gcov/kcov instrumentation provide an early memmove function which will be used to save ipl parameters. The verification if these parameters are actually valid will be done later. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-26Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-11/+14
Pull s390 updates from Martin Schwidefsky: "There are a couple of new things for s390 with this merge request: - a new scheduling domain "drawer" is added to reflect the unusual topology found on z13 machines. Performance tests showed up to 8 percent gain with the additional domain. - the new crc-32 checksum crypto module uses the vector-galois-field multiply and sum SIMD instruction to speed up crc-32 and crc-32c. - proper __ro_after_init support, this requires RO_AFTER_INIT_DATA in the generic vmlinux.lds linker script definitions. - kcov instrumentation support. A prerequisite for that is the inline assembly basic block cleanup, which is the reason for the net/iucv/iucv.c change. - support for 2GB pages is added to the hugetlbfs backend. Then there are two removals: - the oprofile hardware sampling support is dead code and is removed. The oprofile user space uses the perf interface nowadays. - the ETR clock synchronization is removed, this has been superseeded be the STP clock synchronization. And it always has been "interesting" code.. And the usual bug fixes and cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (82 commits) s390/pci: Delete an unnecessary check before the function call "pci_dev_put" s390/smp: clean up a condition s390/cio/chp : Remove deprecated create_singlethread_workqueue s390/chsc: improve channel path descriptor determination s390/chsc: sanitize fmt check for chp_desc determination s390/cio: make fmt1 channel path descriptor optional s390/chsc: fix ioctl CHSC_INFO_CU command s390/cio/device_ops: fix kernel doc s390/cio: allow to reset channel measurement block s390/console: Make preferred console handling more consistent s390/mm: fix gmap tlb flush issues s390/mm: add support for 2GB hugepages s390: have unique symbol for __switch_to address s390/cpuinfo: show maximum thread id s390/ptrace: clarify bits in the per_struct s390: stack address vs thread_info s390: remove pointless load within __switch_to s390: enable kcov support s390/cpumf: use basic block for ecctr inline assembly s390/hypfs: use basic block for diag inline assembly ...
2016-06-28Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"Michael Holzheu1-7/+0
This reverts commit 852ffd0f4e23248b47531058e531066a988434b5. There are use cases where an intermediate boot kernel (1) uses kexec to boot the final production kernel (2). For this scenario we should provide the original boot information to the production kernel (2). Therefore clearing the boot information during kexec() should not be done. Cc: stable@vger.kernel.org # v3.17+ Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/ipl: rename diagnose enumsHeiko Carstens1-8/+8
Rename DIAG308_IPL and DIAG308_DUMP to DIAG308_LOAD_CLEAR and DIAG308_LOAD_NORMAL_DUMP to better reflect the associated IPL functions. Suggested-by: Cornelia Huck <cornelia.huck@de.ibm.com> Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/ipl: use load normal for LPAR re-iplHeiko Carstens1-1/+4
Avoid clearing memory for CCW-type re-ipl within a logical partition. This can save a significant amount of time if a logical partition contains a lot of memory. On the other hand we still clear memory if running within a second level hypervisor, since the hypervisor can simply free all memory that was used for the guest. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390: avoid extable collisionsHeiko Carstens1-1/+1
We have some inline assemblies where the extable entry points to a label at the end of an inline assembly which is not followed by an instruction. On the other hand we have also inline assemblies where the extable entry points to the first instruction of an inline assembly. If a first type inline asm (extable point to empty label at the end) would be directly followed by a second type inline asm (extable points to first instruction) then we would have two different extable entries that point to the same instruction but would have a different target address. This can lead to quite random behaviour, depending on sorting order. I verified that we currently do not have such collisions within the kernel. However to avoid such subtle bugs add a couple of nop instructions to those inline assemblies which contain an extable that points to an empty label. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390: use __section macro everywhereHeiko Carstens1-3/+3
Small cleanup patch to use the shorter __section macro everywhere. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19s390: remove all usages of PSW_ADDR_AMODEHeiko Carstens1-2/+2
This is a leftover from the 31 bit area. For CONFIG_64BIT the usual operation "y = x | PSW_ADDR_AMODE" is a nop. Therefore remove all usages of PSW_ADDR_AMODE and make the code a bit less confusing. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2016-01-11s390: rename struct _lowcore to struct lowcoreHeiko Carstens1-2/+2
Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27s390/dump: rework CPU register dump codeMartin Schwidefsky1-16/+1
To collect the CPU registers of the crashed system allocated a single page with memblock_alloc_base and use it as a copy buffer. Replace the stop-and-store-status sigp with a store-status-at-address sigp in smp_save_dump_cpus() and smp_store_status(). In both cases the target CPU is already stopped and store-status-at-address avoids the detour via the absolute zero page. For kexec simplify s390_reset_system and call store_status() before the prefix register of the boot CPU has been set to zero. Use STPX to store the prefix register and remove dump_prefix_page. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11s390: add support for ipl devices in subchannel sets > 0Sebastian Ott1-11/+37
Allow to ipl from CCW based devices residing in any subchannel set. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11s390/ipl: fix out of bounds access in scpdata_writeSebastian Ott1-12/+5
The input buffer in reipl_fcp_scpdata_write is accessed out of bounds when an offset is specified. The problem is that the offset refers to the data we should write to and not to the buffer we read from. So instead of memcpy(scp_data, buf + off, count); we could just do memcpy(scp_data + off, buf, count); However we not only modify the data but also store its length. For this to work we'd need to remember a state per open FH. Since that's not possible with sysfs callbacks let's just fail when an offset is specified. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/diag: add a statistic for diagnose callsMartin Schwidefsky1-1/+8
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose calls have been done by each CPU in the system. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390/ipl: cleanup macro usageSebastian Ott1-19/+11
ipl.c uses 3 different macros to create a sysfs show function for ipl attributes. Define IPL_ATTR_SHOW_FN which is used by all macros. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390/ipl: cleanup shutdown_action attributesSebastian Ott1-31/+20
Use macros wherever applicable and create a shutdown_action attribute group to simplify the code. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390/ipl: cleanup bin attr usageSebastian Ott1-56/+18
Use macros wherever applicable and put bin_attributes inside attribute_groups to simplify/remove some code. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390: remove 31 bit supportHeiko Carstens1-2/+0
Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>