linux-dev/arch/s390/include/asm/mmu_context.h, branch linus/master

s390/mm: ensure switch_mm() is executed with interrupts disabled

2021-06-07T15:06:59Z

Architecture callback switch_mm() is allowed to be called with enabled interrupts. However, our implementation of switch_mm() does not expect that. Let's follow other architectures and make sure switch_mm() is always executed with interrupts disabled, regardless of what happens with the generic kernel code in the future. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

Merge tag 'asm-generic-mmu-context-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

2020-12-16T07:58:04Z

Pull asm-generic mmu-context cleanup from Arnd Bergmann: "This is a cleanup series from Nicholas Piggin, preparing for later changes. The asm/mmu_context.h header are generalized and common code moved to asm-gneneric/mmu_context.h. This saves a bit of code and makes it easier to change in the future" * tag 'asm-generic-mmu-context-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (25 commits) h8300: Fix generic mmu_context build m68k: mmu_context: Fix Sun-3 build xtensa: use asm-generic/mmu_context.h for no-op implementations x86: use asm-generic/mmu_context.h for no-op implementations um: use asm-generic/mmu_context.h for no-op implementations sparc: use asm-generic/mmu_context.h for no-op implementations sh: use asm-generic/mmu_context.h for no-op implementations s390: use asm-generic/mmu_context.h for no-op implementations riscv: use asm-generic/mmu_context.h for no-op implementations powerpc: use asm-generic/mmu_context.h for no-op implementations parisc: use asm-generic/mmu_context.h for no-op implementations openrisc: use asm-generic/mmu_context.h for no-op implementations nios2: use asm-generic/mmu_context.h for no-op implementations nds32: use asm-generic/mmu_context.h for no-op implementations mips: use asm-generic/mmu_context.h for no-op implementations microblaze: use asm-generic/mmu_context.h for no-op implementations m68k: use asm-generic/mmu_context.h for no-op implementations ia64: use asm-generic/mmu_context.h for no-op implementations hexagon: use asm-generic/mmu_context.h for no-op implementations csky: use asm-generic/mmu_context.h for no-op implementations ...

s390/mm: use invalid asce for user space when switching to init_mm

2020-12-09T20:02:08Z

Currently only idle_task_exit() explicitly switches (switch_mm) to init_mm. This causes the kernel asce to be loaded into cr7 and therefore it would be used for potential user space accesses. This is currently no problem since idle_task_exit() is nearly the last thing a CPU executes before it is taken down. However things might change - and therefore make sure that always the invalid asce is used for cr7 when active_mm is init_mm. This makes sure that all potential user space accesses will fail, instead of accessing kernel address space. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens

s390/mm: use invalid asce instead of kernel asce

2020-11-23T11:01:12Z

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 Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens

s390/mm: remove set_fs / rework address space handling

2020-11-23T11:01:12Z

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 Signed-off-by: Heiko Carstens

s390/mm: remove unused clear_user_asce()

2020-11-12T11:11:25Z

Signed-off-by: Heiko Carstens

s390: use asm-generic/mmu_context.h for no-op implementations

2020-10-27T15:02:38Z

Signed-off-by: Nicholas Piggin Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: linux-s390@vger.kernel.org Signed-off-by: Arnd Bergmann

Merge tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2020-04-04T16:45:50Z

Pull s390 updates from Vasily Gorbik: - Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan common io code. - Extend cpuinfo to include topology information. - Add new extended counters for IBM z15 and sampling buffer allocation rework in perf code. - Add control over zeroing out memory during system restart. - CCA protected key block version 2 support and other fixes/improvements in crypto code. - Convert to new fallthrough; annotations. - Replace zero-length arrays with flexible-arrays. - QDIO debugfs and other small improvements. - Drop 2-level paging support optimization for compat tasks. Varios mm cleanups. - Remove broken and unused hibernate / power management support. - Remove fake numa support which does not bring any benefits. - Exclude offline CPUs from CPU topology masks to be more consistent with other architectures. - Prevent last branching instruction address leaking to userspace. - Other small various fixes and improvements all over the code. * tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits) s390/mm: cleanup init_new_context() callback s390/mm: cleanup virtual memory constants usage s390/mm: remove page table downgrade support s390/qdio: set qdio_irq->cdev at allocation time s390/qdio: remove unused function declarations s390/ccwgroup: remove pm support s390/ap: remove power management code from ap bus and drivers s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc s390/mm: cleanup arch_get_unmapped_area() and friends s390/ism: remove pm support s390/cio: use fallthrough; s390/vfio: use fallthrough; s390/zcrypt: use fallthrough; s390: use fallthrough; s390/cpum_sf: Fix wrong page count in error message s390/diag: fix display of diagnose call statistics s390/ap: Remove ap device suspend and resume callbacks s390/pci: Improve handling of unset UID s390/pci: Fix zpci_alloc_domain() over allocation s390/qdio: pass ISC as parameter to chsc_sadc() ...

s390/mm: cleanup init_new_context() callback

2020-03-28T11:46:12Z

The set of values asce_limit may be assigned with is TASK_SIZE_MAX, _REGION1_SIZE, _REGION2_SIZE and 0 as a special case if the callback was called from execve(). Do VM_BUG_ON() if asce_limit is something else. Save few CPU cycles by removing unnecessary asce_limit re-assignment in case of 3-level task and redundant PGD entry type reconstruction. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/mm: cleanup virtual memory constants usage

2020-03-28T11:46:12Z

Remove duplicate definitions and consolidate usage of virutal and address translation constants. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik