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2020-05-08powerpc/uaccess: Don't use "m<>" constraintMichael Ellerman1-1/+1
The "m<>" constraint breaks compilation with GCC 4.6.x era compilers. The use of the constraint allows the compiler to use update-form instructions, however in practice current compilers never generate those forms for any of the current uses of __put_user_asm_goto(). We anticipate that GCC 4.6 will be declared unsupported for building the kernel in the not too distant future. So for now just switch to the "m" constraint. Fixes: 334710b1496a ("powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'") Signed-off-by: Michael Ellerman <[email protected]> Acked-by: Segher Boessenkool <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-07powerpc/xive: Enforce load-after-store ordering when StoreEOI is activeCédric Le Goater1-0/+8
When an interrupt has been handled, the OS notifies the interrupt controller with a EOI sequence. On a POWER9 system using the XIVE interrupt controller, this can be done with a load or a store operation on the ESB interrupt management page of the interrupt. The StoreEOI operation has less latency and improves interrupt handling performance but it was deactivated during the POWER9 DD2.0 timeframe because of ordering issues. We use the LoadEOI today but we plan to reactivate StoreEOI in future architectures. There is usually no need to enforce ordering between ESB load and store operations as they should lead to the same result. E.g. a store trigger and a load EOI can be executed in any order. Assuming the interrupt state is PQ=10, a store trigger followed by a load EOI will return a Q bit. In the reverse order, it will create a new interrupt trigger from HW. In both cases, the handler processing interrupts is notified. In some cases, the XIVE_ESB_SET_PQ_10 load operation is used to disable temporarily the interrupt source (mask/unmask). When the source is reenabled, the OS can detect if interrupts were received while the source was disabled and reinject them. This process needs special care when StoreEOI is activated. The ESB load and store operations should be correctly ordered because a XIVE_ESB_STORE_EOI operation could leave the source enabled if it has not completed before the loads. For those cases, we enforce Load-after-Store ordering with a special load operation offset. To avoid performance impact, this ordering is only enforced when really needed, that is when interrupt sources are temporarily disabled with the XIVE_ESB_SET_PQ_10 load. It should not be needed for other loads. Signed-off-by: Cédric Le Goater <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-07powerpc/32s: Fix build failure with CONFIG_PPC_KUAP_DEBUGChristophe Leroy1-1/+1
gpr2 is not a parametre of kuap_check(), it doesn't exist. Use gpr instead. Fixes: a68c31fc01ef ("powerpc/32s: Implement Kernel Userspace Access Protection") Signed-off-by: Christophe Leroy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/ea599546f2a7771bde551393889e44e6b2632332.1587368807.git.christophe.leroy@c-s.fr
2020-05-06Merge the lockless page table walk rework into nextMichael Ellerman5-18/+50
This merges the lockless page table walk rework series from Aneesh. Because it touches powerpc KVM code we are sharing it with the kvm-ppc tree in our topic/ppc-kvm branch. This is the cover letter from Aneesh: Avoid IPI while updating page table entries. Problem Summary: Slow termination of KVM guest with large guest RAM config due to a large number of IPIs that were caused by clearing level 1 PTE entries (THP) entries. This is shown in the stack trace below. - qemu-system-ppc [kernel.vmlinux] [k] smp_call_function_many - smp_call_function_many - 36.09% smp_call_function_many serialize_against_pte_lookup radix__pmdp_huge_get_and_clear zap_huge_pmd unmap_page_range unmap_vmas unmap_region __do_munmap __vm_munmap sys_munmap system_call __munmap qemu_ram_munmap qemu_anon_ram_free reclaim_ramblock call_rcu_thread qemu_thread_start start_thread __clone Why we need to do IPI when clearing PMD entries: This was added as part of commit: 13bd817bb884 ("powerpc/thp: Serialize pmd clear against a linux page table walk") serialize_against_pte_lookup makes sure that all parallel lockless page table walk completes before we convert a PMD pte entry to regular pmd entry. We end up doing that conversion in the below scenarios 1) __split_huge_zero_page_pmd 2) do_huge_pmd_wp_page_fallback 3) MADV_DONTNEED running parallel to page faults. local_irq_disable and lockless page table walk: The lockless page table walk work with the assumption that we can dereference the page table contents without holding a lock. For this to work, we need to make sure we read the page table contents atomically and page table pages are not going to be freed/released while we are walking the table pages. We can achieve by using a rcu based freeing for page table pages or if the architecture implements broadcast tlbie, we can block the IPI as we walk the page table pages. To support both the above framework, lockless page table walk is done with irq disabled instead of rcu_read_lock() We do have two interface for lockless page table walk, gup fast and __find_linux_pte. This patch series makes __find_linux_pte table walk safe against the conversion of PMD PTE to regular PMD. gup fast: gup fast is already safe against THP split because kernel now differentiate between a pmd split and a compound page split. gup fast can run parallel to a pmd split and we prevent a parallel gup fast to a hugepage split, by freezing the page refcount and failing the speculative page ref increment. Similar to how gup is safe against parallel pmd split, this patch series updates the __find_linux_pte callers to be safe against a parallel pmd split. We do that by enforcing the following rules. 1) Don't reload the pte value, because that can be updated in parallel. 2) Code should be able to work with a stale PTE value and not the recent one. ie, the pte value that we are looking at may not be the latest value in the page table. 3) Before looking at pte value check for _PAGE_PTE bit. We now do this as part of pte_present() check. Performance: This speeds up Qemu guest RAM del/unplug time as below 128 core, 496GB guest: Without patch: munmap start: timer = 13162 ms, PID=7684 munmap finish: timer = 95312 ms, PID=7684 - delta = 82150 ms With patch (upto removing IPI) munmap start: timer = 196449 ms, PID=6681 munmap finish: timer = 196488 ms, PID=6681 - delta = 39ms With patch (with adding the tlb invalidate in pmdp_huge_get_and_clear_full) munmap start: timer = 196345 ms, PID=6879 munmap finish: timer = 196714 ms, PID=6879 - delta = 369ms Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/mm/book3s64: Fix MADV_DONTNEED and parallel page fault raceAneesh Kumar K.V1-0/+5
MADV_DONTNEED holds mmap_sem in read mode and that implies a parallel page fault is possible and the kernel can end up with a level 1 PTE entry (THP entry) converted to a level 0 PTE entry without flushing the THP TLB entry. Most architectures including POWER have issues with kernel instantiating a level 0 PTE entry while holding level 1 TLB entries. The code sequence I am looking at is down_read(mmap_sem) down_read(mmap_sem) zap_pmd_range() zap_huge_pmd() pmd lock held pmd_cleared table details added to mmu_gather pmd_unlock() insert a level 0 PTE entry() tlb_finish_mmu(). Fix this by forcing a tlb flush before releasing pmd lock if this is not a fullmm invalidate. We can safely skip this invalidate for task exit case (fullmm invalidate) because in that case we are sure there can be no parallel fault handlers. This do change the Qemu guest RAM del/unplug time as below 128 core, 496GB guest: Without patch: munmap start: timer = 196449 ms, PID=6681 munmap finish: timer = 196488 ms, PID=6681 - delta = 39ms With patch: munmap start: timer = 196345 ms, PID=6879 munmap finish: timer = 196714 ms, PID=6879 - delta = 369ms Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/kvm/book3s: Use pte_present instead of opencoding _PAGE_PRESENT checkAneesh Kumar K.V1-1/+1
This adds _PAGE_PTE check and makes sure we validate the pte value returned via find_kvm_host_pte. NOTE: this also considers _PAGE_INVALID to the software valid bit. Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/kvm/book3s: Add helper for host page table walkAneesh Kumar K.V1-0/+16
Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/kvm/book3s: Use kvm helpers to walk shadow or secondary tableAneesh Kumar K.V2-1/+4
update kvmppc_hv_handle_set_rc to use find_kvm_nested_guest_pte and find_kvm_secondary_pte Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/kvm/book3s: Add helper to walk partition scoped linux page table.Aneesh Kumar K.V1-0/+13
The locking rules for walking partition scoped table is different from process scoped table. Hence add a helper for secondary linux page table walk and also add check whether we are holding the right locks. Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/hash64: Restrict page table lookup using init_mm with ↵Aneesh Kumar K.V1-2/+1
__flush_hash_table_range This is only used with init_mm currently. Walking init_mm is much simpler because we don't need to handle concurrent page table like other mm_context Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/mm/hash64: use _PAGE_PTE when checking for pte_presentAneesh Kumar K.V1-5/+10
This makes the pte_present check stricter by checking for additional _PAGE_PTE bit. A level 1 pte pointer (THP pte) can be switched to a pointer to level 0 pte page table page by following two operations. 1) THP split. 2) madvise(MADV_DONTNEED) in parallel to page fault. A lockless page table walk need to make sure we can handle such changes gracefully. Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-05powerpc/pkeys: Avoid using lockless page table walkAneesh Kumar K.V1-9/+0
Fetch pkey from vma instead of linux page table. Also document the fact that in some cases the pkey returned in siginfo won't be the same as the one we took keyfault on. Even with linux page table walk, we can end up in a similar scenario. Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-04powerpc/fadump: use static allocation for reserved memory rangesHari Bathini1-1/+3
At times, memory ranges have to be looked up during early boot, when kernel couldn't be initialized for dynamic memory allocation. In fact, reserved-ranges look up is needed during FADump memory reservation. Without accounting for reserved-ranges in reserving memory for FADump, MPIPL boot fails with memory corruption issues. So, extend memory ranges handling to support static allocation and populate reserved memory ranges during early boot. Fixes: dda9dbfeeb7a ("powerpc/fadump: consider reserved ranges while releasing memory") Cc: [email protected] Signed-off-by: Hari Bathini <[email protected]> Reviewed-by: Mahesh Salgaonkar <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-04powerpc/64s: Fix unrecoverable SLB crashes due to preemption checkMichael Ellerman1-1/+19
Hugh reported that his trusty G5 crashed after a few hours under load with an "Unrecoverable exception 380". The crash is in interrupt_return() where we check lazy_irq_pending(), which calls get_paca() and with CONFIG_DEBUG_PREEMPT=y that goes to check_preemption_disabled() via debug_smp_processor_id(). As Nick explained on the list: Problem is MSR[RI] is cleared here, ready to do the last few things for interrupt return where we're not allowed to take any other interrupts. SLB interrupts can happen just about anywhere aside from kernel text, global variables, and stack. When that hits, it appears to be unrecoverable due to RI=0. The problematic access is in preempt_count() which is: return READ_ONCE(current_thread_info()->preempt_count); Because of THREAD_INFO_IN_TASK, current_thread_info() just points to current, so the access is to somewhere in kernel memory, but not on the stack or in .data, which means it can cause an SLB miss. If we take an SLB miss with RI=0 it is fatal. The easiest solution is to add a version of lazy_irq_pending() that doesn't do the preemption check and call it from the interrupt return path. Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C") Reported-by: Hugh Dickins <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-05-01powerpc/uaccess: Implement user_read_access_begin and user_write_access_beginChristophe Leroy3-3/+37
Add support for selective read or write user access with user_read_access_begin/end and user_write_access_begin/end. Signed-off-by: Christophe Leroy <[email protected]> Reviewed-by: Kees Cook <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/6c83af0f0809ef2a955c39ac622767f6cbede035.1585898438.git.christophe.leroy@c-s.fr
2020-04-30powerpc/uaccess: Implement unsafe_copy_to_user() as a simple loopChristophe Leroy1-1/+20
At the time being, unsafe_copy_to_user() is based on raw_copy_to_user() which calls __copy_tofrom_user(). __copy_tofrom_user() is a big optimised function to copy big amount of data. It aligns destinations to cache line in order to use dcbz instruction. Today unsafe_copy_to_user() is called only from filldir(). It is used to mainly copy small amount of data like filenames, so __copy_tofrom_user() is not fit. Also, unsafe_copy_to_user() is used within user_access_begin/end sections. In those section, it is preferable to not call functions. Rewrite unsafe_copy_to_user() as a macro that uses __put_user_goto(). We first perform a loop of long, then we finish with necessary complements. unsafe_copy_to_user() might be used in the near future to copy fixed-size data, like pt_regs structs during signal processing. Having it as a macro allows GCC to optimise it for instead when it knows the size in advance, it can unloop loops, drop complements when the size is a multiple of longs, etc ... Signed-off-by: Christophe Leroy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/fe952112c29bf6a0a2778c9e6bbb4f4afd2c4258.1587143308.git.christophe.leroy@c-s.fr
2020-04-30powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'Christophe Leroy1-9/+52
unsafe_put_user() is designed to take benefit of 'asm goto'. Instead of using the standard __put_user() approach and branch based on the returned error, use 'asm goto' and make the exception code branch directly to the error label. There is no code anymore in the fixup section. This change significantly simplifies functions using unsafe_put_user() Small exemple of the benefit with the following code: struct test { u32 item1; u16 item2; u8 item3; u64 item4; }; int set_test_to_user(struct test __user *test, u32 item1, u16 item2, u8 item3, u64 item4) { unsafe_put_user(item1, &test->item1, failed); unsafe_put_user(item2, &test->item2, failed); unsafe_put_user(item3, &test->item3, failed); unsafe_put_user(item4, &test->item4, failed); return 0; failed: return -EFAULT; } Before the patch: 00000be8 <set_test_to_user>: be8: 39 20 00 00 li r9,0 bec: 90 83 00 00 stw r4,0(r3) bf0: 2f 89 00 00 cmpwi cr7,r9,0 bf4: 40 9e 00 38 bne cr7,c2c <set_test_to_user+0x44> bf8: b0 a3 00 04 sth r5,4(r3) bfc: 2f 89 00 00 cmpwi cr7,r9,0 c00: 40 9e 00 2c bne cr7,c2c <set_test_to_user+0x44> c04: 98 c3 00 06 stb r6,6(r3) c08: 2f 89 00 00 cmpwi cr7,r9,0 c0c: 40 9e 00 20 bne cr7,c2c <set_test_to_user+0x44> c10: 90 e3 00 08 stw r7,8(r3) c14: 91 03 00 0c stw r8,12(r3) c18: 21 29 00 00 subfic r9,r9,0 c1c: 7d 29 49 10 subfe r9,r9,r9 c20: 38 60 ff f2 li r3,-14 c24: 7d 23 18 38 and r3,r9,r3 c28: 4e 80 00 20 blr c2c: 38 60 ff f2 li r3,-14 c30: 4e 80 00 20 blr 00000000 <.fixup>: ... b8: 39 20 ff f2 li r9,-14 bc: 48 00 00 00 b bc <.fixup+0xbc> bc: R_PPC_REL24 .text+0xbf0 c0: 39 20 ff f2 li r9,-14 c4: 48 00 00 00 b c4 <.fixup+0xc4> c4: R_PPC_REL24 .text+0xbfc c8: 39 20 ff f2 li r9,-14 cc: 48 00 00 00 b cc <.fixup+0xcc> d0: 39 20 ff f2 li r9,-14 d4: 48 00 00 00 b d4 <.fixup+0xd4> d4: R_PPC_REL24 .text+0xc18 00000000 <__ex_table>: ... a0: R_PPC_REL32 .text+0xbec a4: R_PPC_REL32 .fixup+0xb8 a8: R_PPC_REL32 .text+0xbf8 ac: R_PPC_REL32 .fixup+0xc0 b0: R_PPC_REL32 .text+0xc04 b4: R_PPC_REL32 .fixup+0xc8 b8: R_PPC_REL32 .text+0xc10 bc: R_PPC_REL32 .fixup+0xd0 c0: R_PPC_REL32 .text+0xc14 c4: R_PPC_REL32 .fixup+0xd0 After the patch: 00000be8 <set_test_to_user>: be8: 90 83 00 00 stw r4,0(r3) bec: b0 a3 00 04 sth r5,4(r3) bf0: 98 c3 00 06 stb r6,6(r3) bf4: 90 e3 00 08 stw r7,8(r3) bf8: 91 03 00 0c stw r8,12(r3) bfc: 38 60 00 00 li r3,0 c00: 4e 80 00 20 blr c04: 38 60 ff f2 li r3,-14 c08: 4e 80 00 20 blr 00000000 <__ex_table>: ... a0: R_PPC_REL32 .text+0xbe8 a4: R_PPC_REL32 .text+0xc04 a8: R_PPC_REL32 .text+0xbec ac: R_PPC_REL32 .text+0xc04 b0: R_PPC_REL32 .text+0xbf0 b4: R_PPC_REL32 .text+0xc04 b8: R_PPC_REL32 .text+0xbf4 bc: R_PPC_REL32 .text+0xc04 c0: R_PPC_REL32 .text+0xbf8 c4: R_PPC_REL32 .text+0xc04 Signed-off-by: Christophe Leroy <[email protected]> Reviewed-by: Segher Boessenkool <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/23e680624680a9a5405f4b88740d2596d4b17c26.1587143308.git.christophe.leroy@c-s.fr
2020-04-30powerpc/uaccess: Evaluate macro arguments once, before user access is allowedNicholas Piggin1-14/+35
get/put_user() can be called with nontrivial arguments. fs/proc/page.c has a good example: if (put_user(stable_page_flags(ppage), out)) { stable_page_flags() is quite a lot of code, including spin locks in the page allocator. Ensure these arguments are evaluated before user access is allowed. This improves security by reducing code with access to userspace, but it also fixes a PREEMPT bug with KUAP on powerpc/64s: stable_page_flags() is currently called with AMR set to allow writes, it ends up calling spin_unlock(), which can call preempt_schedule. But the task switch code can not be called with AMR set (it relies on interrupts saving the register), so this blows up. It's fine if the code inside allow_user_access() is preemptible, because a timer or IPI will save the AMR, but it's not okay to explicitly cause a reschedule. Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection") Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-30powerpc/sysfs: Show idle_purr and idle_spurr for every CPUGautham R. Shenoy1-0/+32
On Pseries LPARs, to calculate utilization, we need to know the [S]PURR ticks when the CPUs were busy or idle. The total PURR and SPURR ticks are already exposed via the per-cpu sysfs files "purr" and "spurr". This patch adds support for exposing the idle PURR and SPURR ticks via new per-cpu sysfs files named "idle_purr" and "idle_spurr". This patch also adds helper functions to accurately read the values of idle_purr and idle_spurr especially from an interrupt context between when the interrupt has occurred between the pseries_idle_prolog() and pseries_idle_epilog(). This will ensure that the idle purr/spurr values corresponding to the latest idle period is accounted for before these values are read. Signed-off-by: Gautham R. Shenoy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-30powerpc/pseries: Account for SPURR ticks on idle CPUsGautham R. Shenoy1-0/+17
On Pseries LPARs, to calculate utilization, we need to know the [S]PURR ticks when the CPUs were busy or idle. Via pseries_idle_prolog(), pseries_idle_epilog(), we track the idle PURR ticks in the VPA variable "wait_state_cycles". This patch extends the support to account for the idle SPURR ticks. Signed-off-by: Gautham R. Shenoy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-30powerpc/idle: Store PURR snapshot in a per-cpu global variableGautham R. Shenoy1-9/+22
Currently when CPU goes idle, we take a snapshot of PURR via pseries_idle_prolog() which is used at the CPU idle exit to compute the idle PURR cycles via the function pseries_idle_epilog(). Thus, the value of idle PURR cycle thus read before pseries_idle_prolog() and after pseries_idle_epilog() is always correct. However, if we were to read the idle PURR cycles from an interrupt context between pseries_idle_prolog() and pseries_idle_epilog() (this will be done in a future patch), then, the value of the idle PURR thus read will not include the cycles spent in the most recent idle period. Thus, in that interrupt context, we will need access to the snapshot of the PURR before going idle, in order to compute the idle PURR cycles for the latest idle duration. In this patch, we save the snapshot of PURR in pseries_idle_prolog() in a per-cpu variable, instead of on the stack, so that it can be accessed from an interrupt context. Signed-off-by: Gautham R. Shenoy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-30powerpc: Move idle_loop_prolog()/epilog() functions to header fileGautham R. Shenoy1-0/+31
Currently prior to entering an idle state on a Linux Guest, the pseries cpuidle driver implement an idle_loop_prolog() and idle_loop_epilog() functions which ensure that idle_purr is correctly computed, and the hypervisor is informed that the CPU cycles have been donated. These prolog and epilog functions are also required in the default idle call, i.e pseries_lpar_idle(). Hence move these accessor functions to a common header file and call them from pseries_lpar_idle(). Since the existing header files such as asm/processor.h have enough clutter, create a new header file asm/idle.h. Finally rename idle_loop_prolog() and idle_loop_epilog() to pseries_idle_prolog() and pseries_idle_epilog() as they are only relavent for on pseries guests. Signed-off-by: Gautham R. Shenoy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-23arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>Masahiro Yamada2-18/+20
As the bug report [1] pointed out, <linux/vermagic.h> must be included after <linux/module.h>. I believe we should not impose any include order restriction. We often sort include directives alphabetically, but it is just coding style convention. Technically, we can include header files in any order by making every header self-contained. Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in <asm/module.h>, which is not included from <linux/vermagic.h>. Hence, the straight-forward fix-up would be as follows: |--- a/include/linux/vermagic.h |+++ b/include/linux/vermagic.h |@@ -1,5 +1,6 @@ | /* SPDX-License-Identifier: GPL-2.0 */ | #include <generated/utsrelease.h> |+#include <linux/module.h> | | /* Simply sanity version stamp for modules. */ | #ifdef CONFIG_SMP This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC definitions into <asm/vermagic.h>. With this, <linux/module.h> and <linux/vermagic.h> will be orthogonal, and the location of MODULE_ARCH_VERMAGIC definitions will be consistent. For arc and ia64, MODULE_PROC_FAMILY is only used for defining MODULE_ARCH_VERMAGIC. I squashed it. For hexagon, nds32, and xtensa, I removed <asm/modules.h> entirely because they contained nothing but MODULE_ARCH_VERMAGIC definition. Kbuild will automatically generate <asm/modules.h> at build-time, wrapping <asm-generic/module.h>. [1] https://lore.kernel.org/lkml/[email protected] Reported-by: Borislav Petkov <[email protected]> Signed-off-by: Masahiro Yamada <[email protected]> Acked-by: Jessica Yu <[email protected]>
2020-04-20crypto/nx: Remove 'pid' in vas_tx_win_attr structHaren Myneni1-1/+0
When window is opened, pid reference is taken for user space windows. Not needed for kernel windows. So remove 'pid' in vas_tx_win_attr struct. Signed-off-by: Haren Myneni <[email protected]> Acked-by: Herbert Xu <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/1587114674.2275.1132.camel@hbabu-laptop
2020-04-20powerpc/vas: Add VAS user space APIHaren Myneni1-0/+12
On power9, userspace can send GZIP compression requests directly to NX once kernel establishes NX channel / window with VAS. This patch provides user space API which allows user space to establish channel using open VAS_TX_WIN_OPEN ioctl, mmap and close operations. Each window corresponds to file descriptor and application can open multiple windows. After the window is opened, VAS_TX_WIN_OPEN icoctl to open a window on specific VAS instance, mmap() system call to map the hardware address of engine's request queue into the application's virtual address space. Then the application can then submit one or more requests to the the engine by using the copy/paste instructions and pasting the CRBs to the virtual address (aka paste_address) returned by mmap(). Only NX GZIP coprocessor type is supported right now and allow GZIP engine access via /dev/crypto/nx-gzip device node. Thanks to Michael Ellerman for his changes and suggestions to make the ioctl generic to support any coprocessor type. Signed-off-by: Sukadev Bhattiprolu <[email protected]> Signed-off-by: Haren Myneni <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/1587114121.2275.1109.camel@hbabu-laptop
2020-04-20powerpc: Use mm_context vas_windows counter to issue CP_ABORTHaren Myneni4-3/+33
set_thread_uses_vas() sets used_vas flag for a process that opened VAS window and issue CP_ABORT during context switch for only that process. In multi-thread application, windows can be shared. For example Thread A can open a window and Thread B can run COPY/PASTE instructions to send NX request which may cause corruption or snooping or a covert channel Also once this flag is set, continue to run CP_ABORT even the VAS window is closed. So define vas-windows counter in process mm_context, increment this counter for each window open and decrement it for window close. If vas-windows is set, issue CP_ABORT during context switch. It means clear the foreign real address mapping only if the process / thread uses COPY/PASTE. Then disable it for that process if windows are not open. Moved set_thread_uses_vas() code to vas_tx_win_open() as this functionality is needed only for userspace open windows. We are adding VAS userspace support along with this fix. So no need to include this fix in stable releases. Fixes: 9d2a4d71332c ("powerpc: Define set_thread_uses_vas()") Signed-off-by: Haren Myneni <[email protected]> Reported-by: Nicholas Piggin <[email protected]> Suggested-by: Milton Miller <[email protected]> Suggested-by: Nicholas Piggin <[email protected]> Reviewed-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/1587017291.2275.1077.camel@hbabu-laptop
2020-04-20powerpc/vas: Define nx_fault_stamp in coprocessor_request_blockHaren Myneni1-2/+18
Kernel sets fault address and status in CRB for NX page fault on user space address after processing page fault. User space gets the signal and handles the fault mentioned in CRB by bringing the page in to memory and send NX request again. Signed-off-by: Sukadev Bhattiprolu <[email protected]> Signed-off-by: Haren Myneni <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/1587016769.2275.1048.camel@hbabu-laptop
2020-04-20powerpc/xive: Define xive_native_alloc_irq_on_chip()Haren Myneni1-1/+8
This function allocates IRQ on a specific chip. VAS needs per chip IRQ allocation and will have IRQ handler per VAS instance. Signed-off-by: Haren Myneni <[email protected]> Reviewed-by: Cédric Le Goater <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/1587016720.2275.1047.camel@hbabu-laptop
2020-04-10powerpc/mm: thread pgprot_t through create_section_mapping()Logan Gunthorpe3-3/+6
In prepartion to support a pgprot_t argument for arch_add_memory(). Signed-off-by: Logan Gunthorpe <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Eric Badger <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-10mm/vma: define a default value for VM_DATA_DEFAULT_FLAGSAnshuman Khandual2-12/+4
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the existing VM_STACK_DEFAULT_FLAGS. While here, also define some more macros with standard VMA access flag combinations that are used frequently across many platforms. Apart from simplification, this reduces code duplication as well. Signed-off-by: Anshuman Khandual <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]> Cc: Richard Henderson <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Russell King <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Mark Salter <[email protected]> Cc: Guo Ren <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Brian Cain <[email protected]> Cc: Tony Luck <[email protected]> Cc: Michal Simek <[email protected]> Cc: Ralf Baechle <[email protected]> Cc: Paul Burton <[email protected]> Cc: Nick Hu <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Rich Felker <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Jeff Dike <[email protected]> Cc: Chris Zankel <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-09Merge tag 'powerpc-5.7-2' of ↵Linus Torvalds2-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "The bulk of this is the series to make CONFIG_COMPAT user-selectable, it's been around for a long time but was blocked behind the syscall-in-C series. Plus there's also a few fixes and other minor things. Summary: - A fix for a crash in machine check handling on pseries (ie. guests) - A small series to make it possible to disable CONFIG_COMPAT, and turn it off by default for ppc64le where it's not used. - A few other miscellaneous fixes and small improvements. Thanks to: Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann, Christophe Leroy, Dan Carpenter, Ganesh Goudar, Geert Uytterhoeven, Geoff Levand, Mahesh Salgaonkar, Markus Elfring, Michal Suchanek, Nicholas Piggin, Stephen Boyd, Wen Xiong" * tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: selftests/powerpc: Always build the tm-poison test 64-bit powerpc: Improve ppc_save_regs() Revert "powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled" powerpc/time: Replace <linux/clk-provider.h> by <linux/of_clk.h> powerpc/pseries/ddw: Extend upper limit for huge DMA window for persistent memory powerpc/perf: split callchain.c by bitness powerpc/64: Make COMPAT user-selectable disabled on littleendian by default. powerpc/64: make buildable without CONFIG_COMPAT powerpc/perf: consolidate valid_user_sp -> invalid_user_sp powerpc/perf: consolidate read_user_stack_32 powerpc: move common register copy functions from signal_32.c to signal.c powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro powerpc/ps3: Set CONFIG_UEVENT_HELPER=y in ps3_defconfig powerpc/ps3: Remove an unneeded NULL check powerpc/ps3: Remove duplicate error message powerpc/powernv: Re-enable imc trace-mode in kernel powerpc/perf: Implement a global lock to avoid races between trace, core and thread imc events. powerpc/pseries: Fix MCE handling on pseries selftests/eeh: Skip ahci adapters powerpc/64s: Fix doorbell wakeup msgclr optimisation
2020-04-05Merge tag 'powerpc-5.7-1' of ↵Linus Torvalds30-92/+168
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly late as I had to rebase mid-week to insert a bug fix: - A large series from Nick for 64-bit to further rework our exception vectors, and rewrite portions of the syscall entry/exit and interrupt return in C. The result is much easier to follow code that is also faster in general. - Cleanup of our ptrace code to split various parts out that had become badly intertwined with #ifdefs over the years. - Changes to our NUMA setup under the PowerVM hypervisor which should hopefully avoid non-sensical topologies which can lead to warnings from the workqueue code and other problems. - MAINTAINERS updates to remove some of our old orphan entries and update the status of others. - Quite a few other small changes and fixes all over the map. Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing" * tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits) powerpc: Make setjmp/longjmp signature standard powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type powerpc: Suppress .eh_frame generation powerpc: Drop -fno-dwarf2-cfi-asm powerpc/32: drop unused ISA_DMA_THRESHOLD powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces selftests/powerpc: Fix try-run when source tree is not writable powerpc/vmlinux.lds: Explicitly retain .gnu.hash powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c powerpc/ptrace: create ppc_gethwdinfo() powerpc/ptrace: create ptrace_get_debugreg() powerpc/ptrace: split out ADV_DEBUG_REGS related functions. powerpc/ptrace: move register viewing functions out of ptrace.c powerpc/ptrace: split out TRANSACTIONAL_MEM related functions. powerpc/ptrace: split out SPE related functions. powerpc/ptrace: split out ALTIVEC related functions. powerpc/ptrace: split out VSX related functions. powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64 powerpc/ptrace: remove unused header includes ...
2020-04-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds4-14/+17
Pull kvm updates from Paolo Bonzini: "ARM: - GICv4.1 support - 32bit host removal PPC: - secure (encrypted) using under the Protected Execution Framework ultravisor s390: - allow disabling GISA (hardware interrupt injection) and protected VMs/ultravisor support. x86: - New dirty bitmap flag that sets all bits in the bitmap when dirty page logging is enabled; this is faster because it doesn't require bulk modification of the page tables. - Initial work on making nested SVM event injection more similar to VMX, and less buggy. - Various cleanups to MMU code (though the big ones and related optimizations were delayed to 5.8). Instead of using cr3 in function names which occasionally means eptp, KVM too has standardized on "pgd". - A large refactoring of CPUID features, which now use an array that parallels the core x86_features. - Some removal of pointer chasing from kvm_x86_ops, which will also be switched to static calls as soon as they are available. - New Tigerlake CPUID features. - More bugfixes, optimizations and cleanups. Generic: - selftests: cleanups, new MMU notifier stress test, steal-time test - CSV output for kvm_stat" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits) x86/kvm: fix a missing-prototypes "vmread_error" KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y KVM: VMX: Add a trampoline to fix VMREAD error handling KVM: SVM: Annotate svm_x86_ops as __initdata KVM: VMX: Annotate vmx_x86_ops as __initdata KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup() KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes KVM: VMX: Configure runtime hooks using vmx_x86_ops KVM: VMX: Move hardware_setup() definition below vmx_x86_ops KVM: x86: Move init-only kvm_x86_ops to separate struct KVM: Pass kvm_init()'s opaque param to additional arch funcs s390/gmap: return proper error code on ksm unsharing KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move() KVM: Fix out of range accesses to memslots KVM: X86: Micro-optimize IPI fastpath delay KVM: X86: Delay read msr data iff writes ICR MSR KVM: PPC: Book3S HV: Add a capability for enabling secure guests KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs ...
2020-04-02asm-generic: make more kernel-space headers mandatoryMasahiro Yamada1-4/+0
Change a header to mandatory-y if both of the following are met: [1] At least one architecture (except um) specifies it as generic-y in arch/*/include/asm/Kbuild [2] Every architecture (except um) either has its own implementation (arch/*/include/asm/*.h) or specifies it as generic-y in arch/*/include/asm/Kbuild This commit was generated by the following shell script. ----------------------------------->8----------------------------------- arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d') tmpfile=$(mktemp) grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile find arch -path 'arch/*/include/asm/Kbuild' | xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u | while read header do mandatory=yes for arch in $arches do if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild && ! [ -f arch/$arch/include/asm/$header ]; then mandatory=no break fi done if [ "$mandatory" = yes ]; then echo "mandatory-y += $header" >> $tmpfile for arch in $arches do sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild done fi done sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild LANG=C sort $tmpfile >> include/asm-generic/Kbuild ----------------------------------->8----------------------------------- One obvious benefit is the diff stat: 25 files changed, 52 insertions(+), 557 deletions(-) It is tedious to list generic-y for each arch that needs it. So, mandatory-y works like a fallback default (by just wrapping asm-generic one) when arch does not have a specific header implementation. See the following commits: def3f7cefe4e81c296090e1722a76551142c227c a1b39bae16a62ce4aae02d958224f19316d98b24 It is tedious to convert headers one by one, so I processed by a shell script. Signed-off-by: Masahiro Yamada <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Michal Simek <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Arnd Bergmann <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-03powerpc/64: make buildable without CONFIG_COMPATMichal Suchanek1-2/+2
There are numerous references to 32bit functions in generic and 64bit code so ifdef them out. Signed-off-by: Michal Suchanek <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/e5619617020ef3a1f54f0c076e7d74cb9ec9f3bf.1584699455.git.msuchanek@suse.de
2020-04-03powerpc: Add back __ARCH_WANT_SYS_LLSEEK macroMichal Suchanek1-0/+1
This partially reverts commit caf6f9c8a326 ("asm-generic: Remove unneeded __ARCH_WANT_SYS_LLSEEK macro") When CONFIG_COMPAT is disabled on ppc64 the kernel does not build. There is resistance to both removing the llseek syscall from the 64bit syscall tables and building the llseek interface unconditionally. Signed-off-by: Michal Suchanek <[email protected]> Reviewed-by: Arnd Bergmann <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/lkml/[email protected]/ Link: https://lore.kernel.org/lkml/20190829214319.498c7de2@naga/ Link: https://lore.kernel.org/r/dd4575c51e31766e87f7e7fa121d099ab78d3290.1584699455.git.msuchanek@suse.de
2020-04-01powerpc: Make setjmp/longjmp signature standardClement Courbet1-2/+4
Declaring setjmp()/longjmp() as taking longs makes the signature non-standard, and makes clang complain. In the past, this has been worked around by adding -ffreestanding to the compile flags. The implementation looks like it only ever propagates the value (in longjmp) or sets it to 1 (in setjmp), and we only call longjmp with integer parameters. This allows removing -ffreestanding from the compilation flags. Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp") Cc: [email protected] # v4.14+ Signed-off-by: Clement Courbet <[email protected]> Reviewed-by: Nathan Chancellor <[email protected]> Tested-by: Nathan Chancellor <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/32: drop unused ISA_DMA_THRESHOLDMike Rapoport1-2/+1
The ISA_DMA_THRESHOLD variable is set by several platforms but never referenced. Remove it. Signed-off-by: Mike Rapoport <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64Christophe Leroy1-0/+2
Drop a bunch of #ifdefs CONFIG_PPC64 that are not vital. Signed-off-by: Christophe Leroy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/af38b87a7e1e3efe4f9b664eaeb029e6e7d69fdb.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/64s: Implement interrupt exit logic in CNicholas Piggin4-0/+19
Implement the bulk of interrupt return logic in C. The asm return code must handle a few cases: restoring full GPRs, and emulating stack store. The stack store emulation is significantly simplfied, rather than creating a new return frame and switching to that before performing the store, it uses the PACA to keep a scratch register around to perform the store. The asm return code is moved into 64e for now. The new logic has made allowance for 64e, but I don't have a full environment that works well to test it, and even booting in emulated qemu is not great for stress testing. 64e shouldn't be too far off working with this, given a bit more testing and auditing of the logic. This is slightly faster on a POWER9 (page fault speed increases about 1.1%), probably due to reduced mtmsrd. mpe: Includes fixes from Nick for _TIF_EMULATE_STACK_STORE handling (including the fast_interrupt_return path), to remove trace_hardirqs_on(), and fixes the interrupt-return part of the MSR_VSX restore bug caught by tm-unavailable selftest. mpe: Incorporate fix from Nick: The return-to-kernel path has to replay any soft-pending interrupts if it is returning to a context that had interrupts soft-enabled. It has to do this carefully and avoid plain enabling interrupts if this is an irq context, which can cause multiple nesting of interrupts on the stack, and other unexpected issues. The code which avoided this case got the soft-mask state wrong, and marked interrupts as enabled before going around again to retry. This seems to be mostly harmless except when PREEMPT=y, this calls preempt_schedule_irq with irqs apparently enabled and runs into a BUG in kernel/sched/core.c Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michal Suchanek <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/64: Implement soft interrupt replay in CNicholas Piggin1-1/+0
When local_irq_enable() finds a pending soft-masked interrupt, it "replays" it by setting up registers like the initial interrupt entry, then calls into the low level handler to set up an interrupt stack frame and process the interrupt. This is not necessary, and uses more stack than needed. The high level interrupt handler can be called directly from C, with just pt_regs set up on stack. This should be faster and use less stack. Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/64/sycall: Implement syscall entry/exit logic in CNicholas Piggin8-12/+66
System call entry and particularly exit code is beyond the limit of what is reasonable to implement in asm. This conversion moves all conditional branches out of the asm code, except for the case that all GPRs should be restored at exit. Null syscall test is about 5% faster after this patch, because the exit work is handled under local_irq_disable, and the hard mask and pending interrupt replay is handled after that, which avoids games with MSR. mpe: Includes subsequent fixes from Nick: This fixes 4 issues caught by TM selftests. First was a tm-syscall bug that hit due to tabort_syscall being called after interrupts were reconciled (in a subsequent patch), which led to interrupts being enabled before tabort_syscall was called. Rather than going through an un-reconciling interrupts for the return, I just go back to putting the test early in asm, the C-ification of that wasn't a big win anyway. Second is the syscall return _TIF_USER_WORK_MASK check would go into an infinite loop if _TIF_RESTORE_TM became set. The asm code uses _TIF_USER_WORK_MASK to brach to slowpath which includes restore_tm_state. Third is system call return was not calling restore_tm_state, I missed this completely (alhtough it's in the return from interrupt C conversion because when the asm syscall code encountered problems it would branch to the interrupt return code. Fourth is MSR_VEC missing from restore_math, which was caught by tm-unavailable selftest taking an unexpected facility unavailable interrupt when testing VSX unavailble exception with MSR.FP=1 MSR.VEC=1. Fourth case also has a fixup in a subsequent patch. Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michal Suchanek <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/64s/exception: Avoid touching the stack in hdecrementerNicholas Piggin1-1/+0
The hdec interrupt handler is reported to sometimes fire in Linux if KVM leaves it pending after a guest exists. This is harmless, so there is a no-op handler for it. The interrupt handler currently uses the regular kernel stack. Change this to avoid touching the stack entirely. This should be the last place where the regular Linux stack can be accessed with asynchronous interrupts (including PMI) soft-masked. It might be possible to take advantage of this invariant, e.g., to context switch the kernel stack SLB entry without clearing MSR[EE]. Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-04-01powerpc/64s/exception: Move real to virt switch into the common handlerNicholas Piggin1-4/+0
The real mode interrupt entry points currently use rfid to branch to the common handler in virtual mode. This is a significant amount of code, and forces other code (notably the KVM test) to live in the real mode handler. In the interest of minimising the amount of code that runs unrelocated move the switch to virt mode into the common code, and do it with mtmsrd, which avoids clobbering SRRs (although the post-KVMTEST performance of real-mode interrupt handlers is not a big concern these days). This requires CTR to always be saved (real-mode needs to reach 0xc...) but that's not a huge impact these days. It could be optimized away in future. mpe: Incorporate fix from Nick: It's possible for interrupts to be replayed when TM is enabled and suspended, for example rt_sigreturn, where the mtmsrd MSR_KERNEL in the real-mode entry point to the common handler causes a TM Bad Thing exception (due to attempting to clear suspended). The fix for this is to have replay interrupts go to the _virt entry point and skip the mtmsrd, which matches what happens before this patch. Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-03-31Merge tag 'kvm-ppc-next-5.7-1' of ↵Paolo Bonzini4-3/+11
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD KVM PPC update for 5.7 * Add a capability for enabling secure guests under the Protected Execution Framework ultravisor * Various bug fixes and cleanups.
2020-03-31Merge tag 'kvmarm-5.7' of ↵Paolo Bonzini2-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for Linux 5.7 - GICv4.1 support - 32bit host removal
2020-03-28Merge branch 'uaccess.futex' of ↵Thomas Gleixner1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into locking/core Pull uaccess futex cleanups for Al Viro: Consolidate access_ok() usage and the futex uaccess function zoo.
2020-03-27futex: arch_futex_atomic_op_inuser() calling conventions changeAl Viro1-3/+2
Move access_ok() in and pagefault_enable()/pagefault_disable() out. Mechanical conversion only - some instances don't really need a separate access_ok() at all (e.g. the ones only using get_user()/put_user(), or architectures where access_ok() is always true); we'll deal with that in followups. Signed-off-by: Al Viro <[email protected]>
2020-03-27powerpc/64: Avoid isync in flush_dcache_range()Aneesh Kumar K.V1-5/+1
As per ISA an isync is only needed on instruction cache block invalidate. Remove the same from dcache invalidate. Signed-off-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-03-27powerpc/pseries: Handle UE event for memcpy_mcsafeGanesh Goudar1-0/+2
memcpy_mcsafe has been implemented for power machines which is used by pmem infrastructure, so that an UE encountered during memcpy from pmem devices would not result in panic instead a right error code is returned. The implementation expects machine check handler to ignore the event and set nip to continue the execution from fixup code. Appropriate changes are already made to powernv machine check handler, make similar changes to pseries machine check handler to ignore the the event and set nip to continue execution at the fixup entry if we hit UE at an instruction with a fixup entry. while we are at it, have a common function which searches the exception table entry and updates nip with fixup address, and any future common changes can be made in this function that are valid for both architectures. powernv changes are made by commit 895e3dceeb97 ("powerpc/mce: Handle UE event for memcpy_mcsafe") Reviewed-by: Mahesh Salgaonkar <[email protected]> Reviewed-by: Santosh S <[email protected]> Signed-off-by: Ganesh Goudar <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
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