- 13 Jun, 2016 30 commits
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Heiko Carstens authored
On s390 __ro_after_init is currently mapped to __read_mostly which means that data marked as __ro_after_init will not be protected. Reason for this is that the common code __ro_after_init implementation is x86 centric: the ro_after_init data section was added to rodata, since x86 enables write protection to kernel text and rodata very late. On s390 we have write protection for these sections enabled with the initial page tables. So adding the ro_after_init data section to rodata does not work on s390. In order to make __ro_after_init work properly on s390 move the ro_after_init data, right behind rodata. Unlike the rodata section it will be marked read-only later after all init calls happened. This s390 specific implementation adds new __start_ro_after_init and __end_ro_after_init labels. Everything in between will be marked read-only after the init calls happened. In addition to the __ro_after_init data move also the exception table there, since from a practical point of view it fits the __ro_after_init requirements. Signed-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com>
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Heiko Carstens authored
commit c74ba8b3 ("arch: Introduce post-init read-only memory") introduced the __ro_after_init attribute which allows to add variables to the ro_after_init data section. This new section was added to rodata, even though it contains writable data. This in turn causes problems on architectures which mark the page table entries read-only that point to rodata very early. This patch allows architectures to implement an own handling of the .data..ro_after_init section. Usually that would be: - mark the rodata section read-only very early - mark the ro_after_init section read-only within mark_rodata_ro Signed-off-by:
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Martin Schwidefsky authored
ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: -
Martin Schwidefsky authored
The bitmap_equal function has optimized code for small bitmaps with less than BITS_PER_LONG bits. For larger bitmaps the out-of-line function __bitmap_equal is called. For a constant number of bits divisible by BITS_PER_LONG the memcmp function can be used. For s390 gcc knows how to optimize this function, memcmp calls with up to 256 bytes / 2048 bits are translated into a single instruction. Reviewed-by:
David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by:
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Martin Schwidefsky authored
The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: -
Martin Schwidefsky authored
The External-Time-Reference (ETR) clock synchronization interface has been superseded by Server-Time-Protocol (STP). Remove the outdated ETR interface. Signed-off-by: -
Martin Schwidefsky authored
The PTFF instruction can be used to retrieve information about UTC including the current number of leap seconds. Use this value to convert the coordinated server time value of the TOD clock to a proper UTC timestamp to initialize the system time. Without this correction the system time will be off by the number of leap seonds until it has been corrected via NTP. Signed-off-by: -
Martin Schwidefsky authored
It is possible to specify a user offset for the TOD clock, e.g. +2 hours. The TOD clock will carry this offset even if the clock is synchronized with STP. This makes the time stamps acquired with get_sync_clock() useless as another LPAR migth use a different TOD offset. Use the PTFF instrution to get the TOD epoch difference and subtract it from the TOD clock value to get a physical timestamp. As the epoch difference contains the sync check delta as well the LPAR offset value to the physical clock needs to be refreshed after each clock synchronization. Signed-off-by: -
Martin Schwidefsky authored
The PTFF instruction is not a function of ETR, rename and move the PTFF definitions from etr.h to timex.h. Signed-off-by: -
Martin Schwidefsky authored
The sync clock operation of the channel subsystem call for STP delivers the TOD clock difference as a result. Use this TOD clock difference instead of the difference between the TOD timestamps before and after the sync clock operation. Signed-off-by: -
Heiko Carstens authored
Reducing the size of reserved memory for the crash kernel will result in an immediate crash on s390. Reason for that is that we do not create struct pages for memory that is reserved. If that memory is freed any access to struct pages which correspond to this memory will result in invalid memory accesses and a kernel panic. Fix this by properly creating struct pages when the system gets initialized. Change the code also to make use of set_memory_ro() and set_memory_rw() so page tables will be split if required. Signed-off-by:
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Heiko Carstens authored
Implement an s390 version of the weak crash_free_reserved_phys_range function. This allows us to update the size of the reserved crash kernel memory if it will be resized. This was previously done with a call to crash_unmap_reserved_pages from crash_shrink_memory which was removed with ("s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()") Fixes: 7a0058ec ("s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()") Signed-off-by: -
Heiko Carstens authored
The segment/region table that is part of the kernel image must be properly aligned to 16k in order to make the crdte inline assembly work. Otherwise it will calculate a wrong segment/region table start address and access incorrect memory locations if the swapper_pg_dir is not aligned to 16k. Therefore define BSS_FIRST_SECTIONS in order to put the swapper_pg_dir at the beginning of the bss section and also align the bss section to 16k just like other architectures did. Signed-off-by:
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Christian Borntraeger authored
Lets provide the basic machine information for dump_stack on s390. This enables the "Hardware name:" line and results in output like [...] Oops: 0004 ilc:2 [#1] SMP Modules linked in: CPU: 1 PID: 74 Comm: sh Not tainted 4.5.0+ #205 Hardware name: IBM 2964 NC9 704 (KVM) [...] Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Acked-by:
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Daniel van Gerpen authored
Signed-off-by:
Daniel van Gerpen <daniel@vangerpen.de> Acked-by:
Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by:
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Heiko Carstens authored
Show the dynamic and static cpu mhz of each cpu. Since these values are per cpu this requires a fundamental extension of the format of /proc/cpuinfo. Historically we had only a single line per cpu and a summary at the top of the file. This format is hardly extendible if we want to add more per cpu information. Therefore this patch adds per cpu blocks at the end of /proc/cpuinfo: cpu : 0 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 1 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 2 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 3 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 Right now each block contains only the dynamic and static cpu mhz, but it can be easily extended like on every other architecture. This extension is supposed to be compatible with the old format. Signed-off-by:
Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by:
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Heiko Carstens authored
Change the code to print all the current output during the first iteration. This is a preparation patch for the upcoming per cpu block extension to /proc/cpuinfo. Signed-off-by:
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Jason Baron authored
Ensure that we always have __stringify(). Signed-off-by:
Jason Baron <jbaron@akamai.com> Signed-off-by:
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Heiko Carstens authored
Add statistics that show how memory is mapped within the kernel identity mapping. This is more or less the same like git commit ce0c0e50 ("x86, generic: CPA add statistics about state of direct mapping v4") for x86. I also intentionally copied the lower case "k" within DirectMap4k vs the upper case "M" and "G" within the two other lines. Let's have consistent inconsistencies across architectures. The output of /proc/meminfo now contains these additional lines: DirectMap4k: 2048 kB DirectMap1M: 3991552 kB DirectMap2G: 4194304 kB The implementation on s390 is lockless unlike the x86 version, since I assume changes to the kernel mapping are a very rare event. Therefore it really doesn't matter if these statistics could potentially be inconsistent if read while kernel pages tables are being changed. Signed-off-by:
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Heiko Carstens authored
For the kernel identity mapping map everything read-writeable and subsequently call set_memory_ro() to make the ro section read-only. This simplifies the code a lot. Signed-off-by:
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Heiko Carstens authored
set_memory_ro() and set_memory_rw() currently only work on 4k mappings, which is good enough for module code aka the vmalloc area. However we stumbled already twice into the need to make this also work on larger mappings: - the ro after init patch set - the crash kernel resize code Therefore this patch implements automatic kernel page table splitting if e.g. set_memory_ro() would be called on parts of a 2G mapping. This works quite the same as the x86 code, but is much simpler. In order to make this work and to be architecturally compliant we now always use the csp, cspg or crdte instructions to replace valid page table entries. This means that set_memory_ro() and set_memory_rw() will be much more expensive than before. In order to avoid huge latencies the code contains a couple of cond_resched() calls. The current code only splits page tables, but does not merge them if it would be possible. The reason for this is that currently there is no real life scenarion where this would really happen. All current use cases that I know of only change access rights once during the life time. If that should change we can still implement kernel page table merging at a later time. Signed-off-by:
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Heiko Carstens authored
Make pmd_wrprotect() and pmd_mkwrite() available independently from CONFIG_TRANSPARENT_HUGEPAGE and CONFIG_HUGETLB_PAGE so these can be used on the kernel mapping. Also introduce a couple of pud helper functions, namely pud_pfn(), pud_wrprotect(), pud_mkwrite(), pud_mkdirty() and pud_mkclean() which only work on the kernel mapping. Signed-off-by:
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Heiko Carstens authored
Always use PAGE_KERNEL when re-enabling pages within the kernel mapping due to debug pagealloc. Without using this pgprot value pte_mkwrite() and pte_wrprotect() won't work on such mappings after an unmap -> map cycle anymore. Signed-off-by:
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Heiko Carstens authored
Use pte_clear() instead of open-coding it. Signed-off-by:
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Heiko Carstens authored
_REGION3_ENTRY_RO is a duplicate of _REGION_ENTRY_PROTECT. Signed-off-by:
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Heiko Carstens authored
Instead of open-coded SEGMENT_KERNEL and REGION3_KERNEL assignments use defines. Also to make e.g. pmd_wrprotect() work on the kernel mapping a couple more flags must be set. Therefore add the missing flags also. In order to make everything symmetrical this patch also adds software dirty, young, read and write bits for region 3 table entries. Signed-off-by:
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Heiko Carstens authored
Usually segment and region tables are 16k aligned due to the way the buddy allocator works. This is not true for the vmem code which only asks for a 4k alignment. In order to be consistent enforce a 16k alignment here as well. This alignment will be assumed and therefore is required by the pageattr code. Signed-off-by:
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Heiko Carstens authored
We have already two inline assemblies which make use of the csp instruction. Since I need a third instance let's introduce a generic inline assmebly which can be used by everyone. Signed-off-by:
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Muhammad Falak R Wani authored
Use memdup_user_nul to duplicate a memory region from user-space to kernel-space and terminate with a NULL, instead of open coding using kmalloc + copy_from_user and explicitly NULL terminating. Signed-off-by:
Muhammad Falak R Wani <falakreyaz@gmail.com> [heiko.carstens@de.ibm.com: remove comment] Signed-off-by:
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Christian Borntraeger authored
commit 1e133ab2 ("s390/mm: split arch/s390/mm/pgtable.c") factored out the page table handling code from __gmap_zap and __s390_reset_cmma into ptep_zap_unused and added a simple flag that tells which one of the function (reset or not) is to be made. This also changed the behaviour, as it also zaps unused page table entries on reset. Turns out that this is wrong as s390_reset_cmma uses the page walker, which DOES NOT take the ptl lock. The most simple fix is to not do the zapping part on reset (which uses the walker) Signed-off-by:
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- 12 Jun, 2016 4 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linuxLinus Torvalds authored
Pull thermal management fixes from Zhang Rui: - fix an ordering issue in cpu cooling that cooling device is registered before it's ready (freq_table being populated). (Lukasz Luba) - fix a missing comment update (Caesar Wang) * 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: thermal: add the note for set_trip_temp thermal: cpu_cooling: fix improper order during initialization
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block layer fixes from Jens Axboe: "A small collection of fixes for the current series. This contains: - Two fixes for xen-blkfront, from Bob Liu. - A bug fix for NVMe, releasing only the specific resources we requested. - Fix for a debugfs flags entry for nbd, from Josef. - Plug fix from Omar, fixing up a case of code being switched between two functions. - A missing bio_put() for the new discard callers of submit_bio_wait(), fixing a regression causing a leak of the bio. From Shaun. - Improve dirty limit calculation precision in the writeback code, fixing a case where setting a limit lower than 1% of memory would end up being zero. From Tejun" * 'for-linus' of git://git.kernel.dk/linux-block: NVMe: Only release requested regions xen-blkfront: fix resume issues after a migration xen-blkfront: don't call talk_to_blkback when already connected to blkback nbd: pass the nbd pointer for flags debugfs block: missing bio_put following submit_bio_wait blk-mq: really fix plug list flushing for nomerge queues writeback: use higher precision calculation in domain_dirty_limits() -
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull GPIO fixes from Linus Walleij: "A new bunch of GPIO fixes for v4.7. This time I am very grateful that Ricardo Ribalda Delgado went in and fixed my stupid refcounting mistakes in the removal path for GPIO chips. I had a feeling something was wrong here and so it was. It exploded on OMAP and it fixes their problem. Now it should be (more) solid. The rest i compilation, Kconfig and driver fixes. Some tagged for stable. Summary: - Fix a NULL pointer dereference when we are searching the GPIO device list but one of the devices have been removed (struct gpio_chip pointer is NULL). - Fix unaligned reference counters: we were ending on +3 after all said and done. It should be 0. Remove an extraneous get_device(), and call cdev_del() followed by device_del() in gpiochip_remove() instead and the count goes to zero and calls the release() function properly. - Fix a compile warning due to a missing #include in the OF/device tree portions. - Select ANON_INODES for GPIOLIB, we're using that for our character device. Some randconfig tests disclosed the problem. - Make sure the Zynq driver clock runs also without CONFIG_PM enabled - Fix an off-by-one error in the 104-DIO-48E driver - Fix warnings in bcm_kona_gpio_reset()" * tag 'gpio-v4.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: gpio: bcm-kona: fix bcm_kona_gpio_reset() warnings gpio: select ANON_INODES gpio: include <linux/io-mapping.h> in gpiolib-of gpiolib: Fix unaligned used of reference counters gpiolib: Fix NULL pointer deference gpio: zynq: initialize clock even without CONFIG_PM gpio: 104-dio-48e: Fix control port offset computation off-by-one error
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- 11 Jun, 2016 4 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull SCSI fixes from James Bottomley: "Two current fixes: - one affects Qemu CD ROM emulation, which stopped working after the updates in SCSI to require VPD pages from all conformant devices. Fix temporarily by blacklisting Qemu (we can relax later when they come into compliance). - The other is a fix to the optimal transfer size. We set up a minefield for ourselves by being confused about whether the limits are in bytes or sectors (SCSI optimal is in blocks and the queue parameter is in bytes). This tries to fix the problem (wrong setting for queue limits max_sectors) and make the problem more obvious by introducing a wrapper function" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: sd: Fix rw_max for devices that report an optimal xfer size scsi: Add QEMU CD-ROM to VPD Inquiry Blacklist -
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds authored
Pull i2c fixes from Wolfram Sang: - a bigger fix for i801 to finally be able to be loaded on some machines again - smaller driver fixes - documentation update because of a renamed file * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: mux: reg: Provide of_match_table i2c: mux: refer to i2c-mux.txt i2c: octeon: Avoid printk after too long SMBUS message i2c: octeon: Missing AAK flag in case of I2C_M_RECV_LEN i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR
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git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds authored
Pull DeviceTree fixes from Rob Herring: - fix unflatten_dt_nodes when dad parameter is set. - add vendor prefixes for TechNexion and UniWest - documentation fix for Marvell BT - OF IRQ kerneldoc fixes - restrict CMA alignment adjustments to non dma-coherent - a couple of warning fixes in reserved-memory code - DT maintainers updates * tag 'devicetree-fixes-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: drivers: of: add definition of early_init_dt_alloc_reserved_memory_arch drivers/of: Fix depth for sub-tree blob in unflatten_dt_nodes() drivers: of: Fix of_pci.h header guard dt-bindings: Add vendor prefix for TechNexion of: add vendor prefix for UniWest dt: bindings: fix documentation for MARVELL's bt-sd8xxx wireless device of: add missing const for of_parse_phandle_with_args() in !CONFIG_OF of: silence warnings due to max() usage drivers: of: of_reserved_mem: fixup the CMA alignment not to affect dma-coherent of: irq: fix of_irq_get[_byname]() kernel-doc MAINTAINERS: DeviceTree maintainer updates
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Linus Torvalds authored
Merge tag '20160610_uvc_compat_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux Pull uvc compat XU ioctl fixes from Andy Lutomirski: "uvc's compat XU ioctls go through tons of potentially buggy indirection. The first patch removes the indirection. The second one cleans up the code. Compile-tested only. I have the hardware, but I have absolutely no idea what XU does, how to use it, what software to recompile as 32-bit, or what to test in that software" * tag '20160610_uvc_compat_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux: uvc_v4l2: Simplify compat ioctl implementation uvc: Forward compat ioctls to their handlers directly
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- 10 Jun, 2016 2 commits
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Andy Lutomirski authored
The uvc compat ioctl implementation seems to have copied user data for no good reason. Remove a bunch of copies. Signed-off-by:Andy Lutomirski <luto@kernel.org>
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Andy Lutomirski authored
The current code goes through a lot of indirection just to call a known handler. Simplify it: just call the handlers directly. Cc: stable@vger.kernel.org Signed-off-by:
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