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2021-01-19s390: convert to generic entrySven Schnelle
This patch converts s390 to use the generic entry infrastructure from kernel/entry/*. There are a few special things on s390: - PIF_PER_TRAP is moved to TIF_PER_TRAP as the generic code doesn't know about our PIF flags in exit_to_user_mode_loop(). - The old code had several ways to restart syscalls: a) PIF_SYSCALL_RESTART, which was only set during execve to force a restart after upgrading a process (usually qemu-kvm) to pgste page table extensions. b) PIF_SYSCALL, which is set by do_signal() to indicate that the current syscall should be restarted. This is changed so that do_signal() now also uses PIF_SYSCALL_RESTART. Continuing to use PIF_SYSCALL doesn't work with the generic code, and changing it to PIF_SYSCALL_RESTART makes PIF_SYSCALL and PIF_SYSCALL_RESTART more unique. - On s390 calling sys_sigreturn or sys_rt_sigreturn is implemented by executing a svc instruction on the process stack which causes a fault. While handling that fault the fault code sets PIF_SYSCALL to hand over processing to the syscall code on exit to usermode. The patch introduces PIF_SYSCALL_RET_SET, which is set if ptrace sets a return value for a syscall. The s390x ptrace ABI uses r2 both for the syscall number and return value, so ptrace cannot set the syscall number + return value at the same time. The flag makes handling that a bit easier. do_syscall() will just skip executing the syscall if PIF_SYSCALL_RET_SET is set. CONFIG_DEBUG_ASCE was removd in favour of the generic CONFIG_DEBUG_ENTRY. CR1/7/13 will be checked both on kernel entry and exit to contain the correct asces. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-12-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Much x86 work was pushed out to 5.12, but ARM more than made up for it. ARM: - PSCI relay at EL2 when "protected KVM" is enabled - New exception injection code - Simplification of AArch32 system register handling - Fix PMU accesses when no PMU is enabled - Expose CSV3 on non-Meltdown hosts - Cache hierarchy discovery fixes - PV steal-time cleanups - Allow function pointers at EL2 - Various host EL2 entry cleanups - Simplification of the EL2 vector allocation s390: - memcg accouting for s390 specific parts of kvm and gmap - selftest for diag318 - new kvm_stat for when async_pf falls back to sync x86: - Tracepoints for the new pagetable code from 5.10 - Catch VFIO and KVM irqfd events before userspace - Reporting dirty pages to userspace with a ring buffer - SEV-ES host support - Nested VMX support for wait-for-SIPI activity state - New feature flag (AVX512 FP16) - New system ioctl to report Hyper-V-compatible paravirtualization features Generic: - Selftest improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits) KVM: SVM: fix 32-bit compilation KVM: SVM: Add AP_JUMP_TABLE support in prep for AP booting KVM: SVM: Provide support to launch and run an SEV-ES guest KVM: SVM: Provide an updated VMRUN invocation for SEV-ES guests KVM: SVM: Provide support for SEV-ES vCPU loading KVM: SVM: Provide support for SEV-ES vCPU creation/loading KVM: SVM: Update ASID allocation to support SEV-ES guests KVM: SVM: Set the encryption mask for the SVM host save area KVM: SVM: Add NMI support for an SEV-ES guest KVM: SVM: Guest FPU state save/restore not needed for SEV-ES guest KVM: SVM: Do not report support for SMM for an SEV-ES guest KVM: x86: Update __get_sregs() / __set_sregs() to support SEV-ES KVM: SVM: Add support for CR8 write traps for an SEV-ES guest KVM: SVM: Add support for CR4 write traps for an SEV-ES guest KVM: SVM: Add support for CR0 write traps for an SEV-ES guest KVM: SVM: Add support for EFER write traps for an SEV-ES guest KVM: SVM: Support string IO operations for an SEV-ES guest KVM: SVM: Support MMIO for an SEV-ES guest KVM: SVM: Create trace events for VMGEXIT MSR protocol processing KVM: SVM: Create trace events for VMGEXIT processing ...
2020-12-14Merge tag 's390-5.11-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: - Add support for the hugetlb_cma command line option to allocate gigantic hugepages using CMA - Add arch_get_random_long() support. - Add ap bus userspace notifications. - Increase default size of vmalloc area to 512GB and otherwise let it increase dynamically by the size of physical memory. This should fix all occurrences where the vmalloc area was not large enough. - Completely get rid of set_fs() (aka select SET_FS) and rework address space handling while doing that; making address space handling much more simple. - Reimplement getcpu vdso syscall in C. - Add support for extended SCLP responses (> 4k). This allows e.g. to handle also potential large system configurations. - Simplify KASAN by removing 3-level page table support and only supporting 4-levels from now on. - Improve debug-ability of the kernel decompressor code, which now prints also stack traces and symbols in case of problems to the console. - Remove more power management leftovers. - Other various fixes and improvements all over the place. * tag 's390-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (62 commits) s390/mm: add support to allocate gigantic hugepages using CMA s390/crypto: add arch_get_random_long() support s390/smp: perform initial CPU reset also for SMT siblings s390/mm: use invalid asce for user space when switching to init_mm s390/idle: fix accounting with machine checks s390/idle: add missing mt_cycles calculation s390/boot: add build-id to decompressor s390/kexec_file: fix diag308 subcode when loading crash kernel s390/cio: fix use-after-free in ccw_device_destroy_console s390/cio: remove pm support from ccw bus driver s390/cio: remove pm support from css-bus driver s390/cio: remove pm support from IO subchannel drivers s390/cio: remove pm support from chsc subchannel driver s390/vmur: remove unused pm related functions s390/tape: remove unsupported PM functions s390/cio: remove pm support from eadm-sch drivers s390: remove pm support from console drivers s390/dasd: remove unused pm related functions s390/zfcp: remove pm support from zfcp driver s390/ap: let bus_register() add the AP bus sysfs attributes ...
2020-12-10s390/gmap: make gmap memcg awareChristian Borntraeger
gmap allocations can be attributed to a process. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Acked-by: Cornelia Huck <cohuck@redhat.com>
2020-11-23s390/mm: use invalid asce instead of kernel asceHeiko Carstens
Create a region 3 page table which contains only invalid entries, and use that via "s390_invalid_asce" instead of the kernel ASCE whenever there is either - no user address space available, e.g. during early startup - as an intermediate ASCE when address spaces are switched This makes sure that user space accesses in such situations are guaranteed to fail. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-23s390/mm: remove set_fs / rework address space handlingHeiko Carstens
Remove set_fs support from s390. With doing this rework address space handling and simplify it. As a result address spaces are now setup like this: CPU running in | %cr1 ASCE | %cr7 ASCE | %cr13 ASCE ----------------------------|-----------|-----------|----------- user space | user | user | kernel kernel, normal execution | kernel | user | kernel kernel, kvm guest execution | gmap | user | kernel To achieve this the getcpu vdso syscall is removed in order to avoid secondary address mode and a separate vdso address space in for user space. The getcpu vdso syscall will be implemented differently with a subsequent patch. The kernel accesses user space always via secondary address space. This happens in different ways: - with mvcos in home space mode and directly read/write to secondary address space - with mvcs/mvcp in primary space mode and copy from primary space to secondary space or vice versa - with e.g. cs in secondary space mode and access secondary space Switching translation modes happens with sacf before and after instructions which access user space, like before. Lazy handling of control register reloading is removed in the hope to make everything simpler, but at the cost of making kernel entry and exit a bit slower. That is: on kernel entry the primary asce is always changed to contain the kernel asce, and on kernel exit the primary asce is changed again so it contains the user asce. In kernel mode there is only one exception to the primary asce: when kvm guests are executed the primary asce contains the gmap asce (which describes the guest address space). The primary asce is reset to kernel asce whenever kvm guest execution is interrupted, so that this doesn't has to be taken into account for any user space accesses. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-20s390/vmem: make variable and function names consistentAlexander Gordeev
Rename some variable and functions to better clarify what they are and what they do. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-20s390/vmem: remove redundant checkAlexander Gordeev
Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-20s390: unify identity mapping limits handlingVasily Gorbik
Currently we have to consider too many different values which in the end only affect identity mapping size. These are: 1. max_physmem_end - end of physical memory online or standby. Always <= end of the last online memory block (get_mem_detect_end()). 2. CONFIG_MAX_PHYSMEM_BITS - the maximum size of physical memory the kernel is able to support. 3. "mem=" kernel command line option which limits physical memory usage. 4. OLDMEM_BASE which is a kdump memory limit when the kernel is executed as crash kernel. 5. "hsa" size which is a memory limit when the kernel is executed during zfcp/nvme dump. Through out kernel startup and run we juggle all those values at once but that does not bring any amusement, only confusion and complexity. Unify all those values to a single one we should really care, that is our identity mapping size. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-11KVM: s390: pv: Mark mm as protected after the set secure parameters and ↵Janosch Frank
improve cleanup We can only have protected guest pages after a successful set secure parameters call as only then the UV allows imports and unpacks. By moving the test we can now also check for it in s390_reset_acc() and do an early return if it is 0. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Fixes: 29b40f105ec8 ("KVM: s390: protvirt: Add initial vm and cpu lifecycle handling") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-11-09s390/kasan: remove obvious parameter with the only possible valueVasily Gorbik
Kasan early code is only working on init_mm, remove unneeded pgd parameter from kasan_copy_shadow and rename it to kasan_copy_shadow_mapping. Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-09s390/kasan: avoid confusing namingVasily Gorbik
Kasan has nothing to do with vmemmap, strip vmemmap from function names to avoid confusing people. Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-09s390/kasan: remove 3-level paging supportVasily Gorbik
Compiling the kernel with Kasan disables automatic 3-level vs 4-level kernel space paging selection, because the shadow memory offset has to be known at compile time and there is no such offset which would be acceptable for both 3 and 4-level paging. Instead S390_4_LEVEL_PAGING option was introduced which allowed to pick how many paging levels to use under Kasan. With the introduction of protected virtualization, kernel memory layout may be affected due to ultravisor secure storage limit. This adds additional complexity into how memory layout would look like in combination with Kasan predefined shadow memory offsets. To simplify this make Kasan 4-level paging default and remove Kasan 3-level paging support. Suggested-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-23Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio updates from Michael Tsirkin: "vhost, vdpa, and virtio cleanups and fixes A very quiet cycle, no new features" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: MAINTAINERS: add URL for virtio-mem vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call vringh: fix __vringh_iov() when riov and wiov are different vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK s390: virtio: PV needs VIRTIO I/O device protection virtio: let arch advertise guest's memory access restrictions vhost_vdpa: Fix duplicate included kernel.h vhost: reduce stack usage in log_used virtio-mem: Constify mem_id_table virtio_input: Constify id_table virtio-balloon: Constify id_table vdpa/mlx5: Fix failure to bring link up vdpa/mlx5: Make use of a specific 16 bit endianness API
2020-10-21s390: virtio: PV needs VIRTIO I/O device protectionPierre Morel
If protected virtualization is active on s390, VIRTIO has only retricted access to the guest memory. Define CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS and export arch_has_restricted_virtio_memory_access to advertize VIRTIO if that's the case. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Link: https://lore.kernel.org/r/1599728030-17085-3-git-send-email-pmorel@linux.ibm.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-10-16Merge tag 's390-5.10-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Remove address space overrides using set_fs() - Convert to generic vDSO - Convert to generic page table dumper - Add ARCH_HAS_DEBUG_WX support - Add leap seconds handling support - Add NVMe firmware-assisted kernel dump support - Extend NVMe boot support with memory clearing control and addition of kernel parameters - AP bus and zcrypt api code rework. Add adapter configure/deconfigure interface. Extend debug features. Add failure injection support - Add ECC secure private keys support - Add KASan support for running protected virtualization host with 4-level paging - Utilize destroy page ultravisor call to speed up secure guests shutdown - Implement ioremap_wc() and ioremap_prot() with MIO in PCI code - Various checksum improvements - Other small various fixes and improvements all over the code * tag 's390-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (85 commits) s390/uaccess: fix indentation s390/uaccess: add default cases for __put_user_fn()/__get_user_fn() s390/zcrypt: fix wrong format specifications s390/kprobes: move insn_page to text segment s390/sie: fix typo in SIGP code description s390/lib: fix kernel doc for memcmp() s390/zcrypt: Introduce Failure Injection feature s390/zcrypt: move ap_msg param one level up the call chain s390/ap/zcrypt: revisit ap and zcrypt error handling s390/ap: Support AP card SCLP config and deconfig operations s390/sclp: Add support for SCLP AP adapter config/deconfig s390/ap: add card/queue deconfig state s390/ap: add error response code field for ap queue devices s390/ap: split ap queue state machine state from device state s390/zcrypt: New config switch CONFIG_ZCRYPT_DEBUG s390/zcrypt: introduce msg tracking in zcrypt functions s390/startup: correct early pgm check info formatting s390: remove orphaned extern variables declarations s390/kasan: make sure int handler always run with DAT on s390/ipl: add support to control memory clearing for nvme re-IPL ...
2020-10-13arch, drivers: replace for_each_membock() with for_each_mem_range()Mike Rapoport
There are several occurrences of the following pattern: for_each_memblock(memory, reg) { start = __pfn_to_phys(memblock_region_memory_base_pfn(reg); end = __pfn_to_phys(memblock_region_memory_end_pfn(reg)); /* do something with start and end */ } Using for_each_mem_range() iterator is more appropriate in such cases and allows simpler and cleaner code. [akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build] [rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring] Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Axtens <dja@axtens.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13arch, mm: replace for_each_memblock() with for_each_mem_pfn_range()Mike Rapoport
There are several occurrences of the following pattern: for_each_memblock(memory, reg) { start_pfn = memblock_region_memory_base_pfn(reg); end_pfn = memblock_region_memory_end_pfn(reg); /* do something with start_pfn and end_pfn */ } Rather than iterate over all memblock.memory regions and each time query for their start and end PFNs, use for_each_mem_pfn_range() iterator to get simpler and clearer code. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> [.clang-format] Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Axtens <dja@axtens.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: https://lkml.kernel.org/r/20200818151634.14343-12-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-16s390/kasan: support protvirt with 4-level pagingVasily Gorbik
Currently the kernel crashes in Kasan instrumentation code if CONFIG_KASAN_S390_4_LEVEL_PAGING is used on protected virtualization capable machine where the ultravisor imposes addressing limitations on the host and those limitations are lower then KASAN_SHADOW_OFFSET. The problem is that Kasan has to know in advance where vmalloc/modules areas would be. With protected virtualization enabled vmalloc/modules areas are moved down to the ultravisor secure storage limit while kasan still expects them at the very end of 4-level paging address space. To fix that make Kasan recognize when protected virtualization is enabled and predefine vmalloc/modules areas position which are compliant with ultravisor secure storage limit. Kasan shadow itself stays in place and might reside above that ultravisor secure storage limit. One slight difference compaired to a kernel without Kasan enabled is that vmalloc/modules areas position is not reverted to default if ultravisor initialization fails. It would still be below the ultravisor secure storage limit. Kernel layout with kasan, 4-level paging and protected virtualization enabled (ultravisor secure storage limit is at 0x0000800000000000): ---[ vmemmap Area Start ]--- 0x0000400000000000-0x0000400080000000 ---[ vmemmap Area End ]--- ---[ vmalloc Area Start ]--- 0x00007fe000000000-0x00007fff80000000 ---[ vmalloc Area End ]--- ---[ Modules Area Start ]--- 0x00007fff80000000-0x0000800000000000 ---[ Modules Area End ]--- ---[ Kasan Shadow Start ]--- 0x0018000000000000-0x001c000000000000 ---[ Kasan Shadow End ]--- 0x001c000000000000-0x0020000000000000 1P PGD I Kernel layout with kasan, 4-level paging and protected virtualization disabled/unsupported: ---[ vmemmap Area Start ]--- 0x0000400000000000-0x0000400060000000 ---[ vmemmap Area End ]--- ---[ Kasan Shadow Start ]--- 0x0018000000000000-0x001c000000000000 ---[ Kasan Shadow End ]--- ---[ vmalloc Area Start ]--- 0x001fffe000000000-0x001fffff80000000 ---[ vmalloc Area End ]--- ---[ Modules Area Start ]--- 0x001fffff80000000-0x0020000000000000 ---[ Modules Area End ]--- Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-16s390/mm,ptdump: sort markersVasily Gorbik
Kasan configuration options and size of physical memory present could affect kernel memory layout. In particular vmemmap, vmalloc and modules might come before kasan shadow or after it. To make ptdump correctly output markers in the right order markers have to be sorted. To preserve the original order of markers with the same start address avoid using sort() from lib/sort.c (which is not stable sorting algorithm) and sort markers in place. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-16s390/mm,ptdump: add proper ifdefsHeiko Carstens
Use ifdefs instead of IS_ENABLED() to avoid compile error for !PTDUMP_DEBUGFS: arch/s390/mm/dump_pagetables.c: In function ‘pt_dump_init’: arch/s390/mm/dump_pagetables.c:248:64: error: ‘ptdump_fops’ undeclared (first use in this function); did you mean ‘pidfd_fops’? debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, &ptdump_fops); Reported-by: Julian Wiedmann <jwi@linux.ibm.com> Fixes: 08c8e685c7c9 ("s390: add ARCH_HAS_DEBUG_WX support") Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/uv: add destroy page callJanosch Frank
We don't need to export pages if we destroy the VM configuration afterwards anyway. Instead we can destroy the page which will zero it and then make it accessible to the host. Destroying is about twice as fast as the export. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/kvm/20200907124700.10374-2-frankja@linux.ibm.com/ Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/mm,ptdump: add couple of additional markersVasily Gorbik
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> [hca@linux.ibm.com: add more markers, rename some markers] Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/kasan: make shadow memory noexecVasily Gorbik
ARCH_HAS_DEBUG_WX feature support brought attention to the fact that currently initial kasan shadow memory mapped without noexec flag. So fix that. Temporary initial identity mapping is still created without noexec, but it is replaced by properly set up paging later. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390: add ARCH_HAS_DEBUG_WX supportHeiko Carstens
Checks the whole kernel address space for W+X mappings. Note that currently the first lowcore page unfortunately has to be mapped W+X. Therefore this not reported as an insecure mapping. For the very same reason the wording is also different to other architectures if the test passes: On s390 it is "no unexpected W+X pages found" instead of "no W+X pages found". Tested-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/mm,ptdump: make page table dumping seq_file optionalHeiko Carstens
s390 version of ae5d1cf358a5 ("arm64: dump: Make the page table dumping seq_file optional"). Tested-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/mm,ptdump: hold cpa mutex while walking for kernel page table dumpHeiko Carstens
This is currently only preventing that outdated information is provided to user space. A concurrent split of huge/large pages does modify the kernel page tables, however either the huge/large mapping is reported or the split area is being walked. This "fixes" also only a potential future bug, since split pages could also be merged again if page permissions are the same for larger memory areas. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/mm,ptdump: hold memory hotplug lock while walking for kernel page table ↵Heiko Carstens
dump This is the s390 variant of commit bf2b59f60ee1 ("arm64/mm: Hold memory hotplug lock while walking for kernel page table dump"). Right now this doesn't fix any real bug, however as soon as kvm patches get merged which make use of memory remove we might end up dereferencing/accessing freed page tables. Therefore fix this potential bug already now. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/mm,ptdump: convert to generic page table dumperHeiko Carstens
Make use of generic ptdump infrastructure. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390/pci: Implement ioremap_wc/prot() with MIONiklas Schnelle
With our current support for the new MIO PCI instructions, write combining/write back MMIO memory can be obtained via the pci_iomap_wc() and pci_iomap_wc_range() functions. This is achieved by using the write back address for a specific bar as provided in clp_store_query_pci_fn() These functions are however not widely used and instead drivers often rely on ioremap_wc() and ioremap_prot(), which on other platforms enable write combining using a PTE flag set through the pgrprot value. While we do not have a write combining flag in the low order flag bits of the PTE like x86_64 does, with MIO support, there is a write back bit in the physical address (bit 1 on z15) and thus also the PTE. Which bit is used to toggle write back and whether it is available at all, is however not fixed in the architecture. Instead we get this information from the CLP Store Logical Processor Characteristics for PCI command. When the write back bit is not provided we fall back to the existing behavior. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14s390: add 3f program exception handlerJanosch Frank
Program exception 3f (secure storage violation) can only be detected when the CPU is running in SIE with a format 4 state description, e.g. running a protected guest. Because of this and because user space partly controls the guest memory mapping and can trigger this exception, we want to send a SIGSEGV to the process running the guest and not panic the kernel. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Cc: <stable@vger.kernel.org> # 5.7 Fixes: 084ea4d611a3 ("s390/mm: add (non)secure page access exceptions handlers") Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-08-26s390/vmem: fix vmem_add_range for 4-level pagingVasily Gorbik
The kernel currently crashes if 4-level paging is used. Add missing p4d_populate for just allocated pud entry. Fixes: 3e0d3e408e63 ("s390/vmem: consolidate vmem_add_range() and vmem_remove_range()") Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-08-13Merge tag 's390-5.9-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Heiko Carstens: - Allow s390 debug feature to handle finally more than 256 CPU numbers, instead of truncating the most significant bits. - Improve THP splitting required by qemu processes by making use of walk_page_vma() instead of calling follow_page() for every single page within each vma. - Add missing ZCRYPT dependency to VFIO_AP to fix potential compile problems. - Remove not required select CLOCKSOURCE_VALIDATE_LAST_CYCLE again. - Set node distance to LOCAL_DISTANCE instead of 0, since e.g. libnuma translates a node distance of 0 to "no NUMA support available". - Couple of other minor fixes and improvements. * tag 's390-5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/numa: move code to arch/s390/kernel s390/time: remove select CLOCKSOURCE_VALIDATE_LAST_CYCLE again s390/debug: debug feature version 3 s390/Kconfig: add missing ZCRYPT dependency to VFIO_AP s390/numa: set node distance to LOCAL_DISTANCE s390/pkey: remove redundant variable initialization s390/test_unwind: fix possible memleak in test_unwind() s390/gmap: improve THP splitting s390/atomic: circumvent gcc 10 build regression
2020-08-12mm/gup: remove task_struct pointer for all gup codePeter Xu
After the cleanup of page fault accounting, gup does not need to pass task_struct around any more. Remove that parameter in the whole gup stack. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/s390: use general page fault accountingPeter Xu
Use the general page fault accounting by passing regs into handle_mm_fault(). It naturally solve the issue of multiple page fault accounting when page fault retry happened. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Link: http://lkml.kernel.org/r/20200707225021.200906-19-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm: do page fault accounting in handle_mm_faultPeter Xu
Patch series "mm: Page fault accounting cleanups", v5. This is v5 of the pf accounting cleanup series. It originates from Gerald Schaefer's report on an issue a week ago regarding to incorrect page fault accountings for retried page fault after commit 4064b9827063 ("mm: allow VM_FAULT_RETRY for multiple times"): https://lore.kernel.org/lkml/20200610174811.44b94525@thinkpad/ What this series did: - Correct page fault accounting: we do accounting for a page fault (no matter whether it's from #PF handling, or gup, or anything else) only with the one that completed the fault. For example, page fault retries should not be counted in page fault counters. Same to the perf events. - Unify definition of PERF_COUNT_SW_PAGE_FAULTS: currently this perf event is used in an adhoc way across different archs. Case (1): for many archs it's done at the entry of a page fault handler, so that it will also cover e.g. errornous faults. Case (2): for some other archs, it is only accounted when the page fault is resolved successfully. Case (3): there're still quite some archs that have not enabled this perf event. Since this series will touch merely all the archs, we unify this perf event to always follow case (1), which is the one that makes most sense. And since we moved the accounting into handle_mm_fault, the other two MAJ/MIN perf events are well taken care of naturally. - Unify definition of "major faults": the definition of "major fault" is slightly changed when used in accounting (not VM_FAULT_MAJOR). More information in patch 1. - Always account the page fault onto the one that triggered the page fault. This does not matter much for #PF handlings, but mostly for gup. More information on this in patch 25. Patchset layout: Patch 1: Introduced the accounting in handle_mm_fault(), not enabled. Patch 2-23: Enable the new accounting for arch #PF handlers one by one. Patch 24: Enable the new accounting for the rest outliers (gup, iommu, etc.) Patch 25: Cleanup GUP task_struct pointer since it's not needed any more This patch (of 25): This is a preparation patch to move page fault accountings into the general code in handle_mm_fault(). This includes both the per task flt_maj/flt_min counters, and the major/minor page fault perf events. To do this, the pt_regs pointer is passed into handle_mm_fault(). PERF_COUNT_SW_PAGE_FAULTS should still be kept in per-arch page fault handlers. So far, all the pt_regs pointer that passed into handle_mm_fault() is NULL, which means this patch should have no intented functional change. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200707225021.200906-1-peterx@redhat.com Link: http://lkml.kernel.org/r/20200707225021.200906-2-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-11s390/gmap: improve THP splittingGerald Schaefer
During s390_enable_sie(), we need to take care of splitting all qemu user process THP mappings. This is currently done with follow_page(FOLL_SPLIT), by simply iterating over all vma ranges, with PAGE_SIZE increment. This logic is sub-optimal and can result in a lot of unnecessary overhead, especially when using qemu and ASAN with large shadow map. Ilya reported significant system slow-down with one CPU busy for a long time and overall unresponsiveness. Fix this by using walk_page_vma() and directly calling split_huge_pmd() only for present pmds, which greatly reduces overhead. Cc: <stable@vger.kernel.org> # v5.4+ Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-08-07mm/sparse: cleanup the code surrounding memory_present()Mike Rapoport
After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP we have two equivalent functions that call memory_present() for each region in memblock.memory: sparse_memory_present_with_active_regions() and membocks_present(). Moreover, all architectures have a call to either of these functions preceding the call to sparse_init() and in the most cases they are called one after the other. Mark the regions from memblock.memory as present during sparce_init() by making sparse_init() call memblocks_present(), make memblocks_present() and memory_present() functions static and remove redundant sparse_memory_present_with_active_regions() function. Also remove no longer required HAVE_MEMORY_PRESENT configuration option. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200712083130.22919-1-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07mm: remove unneeded includes of <asm/pgalloc.h>Mike Rapoport
Patch series "mm: cleanup usage of <asm/pgalloc.h>" Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in <asm-generic/pgalloc.h> and enable use of the generic functions where appropriate. In addition, functions declared and defined in <asm/pgalloc.h> headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the <asm/pgalloc.h> included all over the place. The first patch in this series removes unneeded includes of <asm/pgalloc.h> In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases <asm/pgalloc.h> header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in <asm/pgalloc.h> and do not require that header. As for the other header files that used to include <asm/pgalloc.h>, it is possible to move that include into the .c file that actually uses symbols from <asm/pgalloc.h> and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [rppt@linux.ibm.com: fix powerpc warning] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-03Merge tag 's390-5.9-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: - Add support for function error injection. - Add support for custom exception handlers, as required by BPF_PROBE_MEM. - Add support for BPF_PROBE_MEM. - Add trace events for idle enter / exit for the s390 specific idle implementation. - Remove unused zcore memmmap device. - Remove unused "raw view" from s390 debug feature. - AP bus + zcrypt device driver code refactoring. - Provide cex4 cca sysfs attributes for cex3 for zcrypt device driver. - Expose only minimal interface to walk physmem for mm/memblock. This is a common code change and it has been agreed on with Mike Rapoport and Andrew Morton that this can go upstream via the s390 tree. - Rework of the s390 vmem/vmmemap code to allow for future memory hot remove. - Get rid of FORCE_MAX_ZONEORDER to finally allow for order-10 allocations again, instead of only order-8 allocations. - Various small improvements and fixes. * tag 's390-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits) s390/vmemmap: coding style updates s390/vmemmap: avoid memset(PAGE_UNUSED) when adding consecutive sections s390/vmemmap: remember unused sub-pmd ranges s390/vmemmap: fallback to PTEs if mapping large PMD fails s390/vmem: cleanup empty page tables s390/vmemmap: take the vmem_mutex when populating/freeing s390/vmemmap: cleanup when vmemmap_populate() fails s390/vmemmap: extend modify_pagetable() to handle vmemmap s390/vmem: consolidate vmem_add_range() and vmem_remove_range() s390/vmem: rename vmem_add_mem() to vmem_add_range() s390: enable HAVE_FUNCTION_ERROR_INJECTION s390/pci: clarify comment in s390_mmio_read/write s390/time: improve comparison for tod steering s390/time: select CLOCKSOURCE_VALIDATE_LAST_CYCLE s390/time: use CLOCKSOURCE_MASK s390/bpf: implement BPF_PROBE_MEM s390/kernel: expand exception table logic to allow new handling options s390/kernel: unify EX_TABLE* implementations s390/mm: allow order 10 allocations s390/mm: avoid trimming to MAX_ORDER ...
2020-07-27s390/vmemmap: coding style updatesHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: avoid memset(PAGE_UNUSED) when adding consecutive sectionsDavid Hildenbrand
Let's avoid memset(PAGE_UNUSED) when adding consecutive sections, whereby the vmemmap of a single section does not span full PMDs. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-10-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: remember unused sub-pmd rangesDavid Hildenbrand
With a memmap size of 56 bytes or 72 bytes per page, the memmap for a 256 MB section won't span full PMDs. As we populate single sections and depopulate single sections, the depopulation step would not be able to free all vmemmap pmds anymore. Do it similarly to x86, marking the unused memmap ranges in a special way (pad it with 0xFD). This allows us to add/remove sections, cleaning up all allocated vmemmap pages even if the memmap size is not multiple of 16 bytes per page. A 56 byte memmap can, for example, be created with !CONFIG_MEMCG and !CONFIG_SLUB. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-9-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: fallback to PTEs if mapping large PMD failsDavid Hildenbrand
Let's fallback to single pages if short on huge pages. No need to stop memory hotplug. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-8-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmem: cleanup empty page tablesDavid Hildenbrand
Let's cleanup empty page tables. Consider only page tables that fully fall into the idendity mapping and the vmemmap range. As there are no valid accesses to vmem/vmemmap within non-populated ranges, the single tlb flush at the end should be sufficient. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-7-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: take the vmem_mutex when populating/freeingDavid Hildenbrand
Let's synchronize all accesses to the 1:1 and vmemmap mappings. This will be especially relevant when wanting to cleanup empty page tables that could be shared by both. Avoid races when removing tables that might be just about to get reused. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-6-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: cleanup when vmemmap_populate() failsDavid Hildenbrand
Cleanup what we partially added in case vmemmap_populate() fails. For vmem, this is already handled by vmem_add_mapping(). Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-5-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmemmap: extend modify_pagetable() to handle vmemmapDavid Hildenbrand
Extend our shiny new modify_pagetable() to handle !direct (vmemmap) mappings. Convert vmemmap_populate() and implement vmemmap_free(). Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-4-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-27s390/vmem: consolidate vmem_add_range() and vmem_remove_range()David Hildenbrand
We want to have only a single pagetable walker and reuse the same functionality for vmemmap handling. Let's start by consolidating vmem_add_range() and vmem_remove_range(), converting it into a recursive implementation. A recursive implementation makes it easier to expand individual cases without harming readability. In addition, we minimize traversing the whole hierarchy over and over again. One change is that we don't unmap large PMDs/PUDs when not completely covered by the request, something that should never happen with direct mappings, unless one would be removing in other granularity than added, which would be broken already. Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20200722094558.9828-3-david@redhat.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>