In order to make use of the CP0_BadInstr & CP0_BadInstrP registers we
need to be a bit more careful not to treat code fetch faults as MMIO,
lest we hit an UNPREDICTABLE register value when we try to emulate the
MMIO load instruction but there was no valid instruction word available
to the hardware.
Add a kvm_is_ifetch_fault() helper to try to figure out whether a load
fault was due to a code fetch, and prevent MMIO instruction emulation in
that case.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
MIPS KVM uses its own variation of get_new_mmu_context() which takes an
extra vcpu pointer (unused) and does exactly the same thing.
Switch to just using get_new_mmu_context() directly and drop KVM's
version of it as it doesn't really serve any purpose.
The nearby declarations of kvm_mips_alloc_new_mmu_context(),
kvm_mips_vcpu_load() and kvm_mips_vcpu_put() are also removed from
kvm_host.h, as no definitions or users exist.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
When exceptions are injected into the MIPS KVM guest, the whole host TLB
is flushed (except any entries in the guest KSeg0 range). This is
certainly not mandated by the architecture when exceptions are taken
(userland can't directly change TLB mappings anyway), and is a pretty
heavyweight operation:
- There may be hundreds of TLB entries especially when a 512 entry FTLB
is present. These are walked and read and conditionally invalidated,
so the TLBINV feature can't be used either.
- It'll indiscriminately wipe out entries belonging to other memory
spaces. A simple ASID regeneration would be much faster to perform,
although it'd wipe out the guest KSeg0 mappings too.
My suspicion is that this was simply to plaster over the fact that
kvm_mips_host_tlb_inv() incorrectly only invalidated TLB entries in the
ASID for guest usermode, and not the ASID for guest kernelmode.
Now that the recent commit "KVM: MIPS/TLB: Flush host TLB entry in
kernel ASID" fixes kvm_mips_host_tlb_inv() to flush TLB entries in the
kernelmode ASID when the guest TLB changes, lets drop these calls and
the otherwise unused kvm_mips_flush_host_tlb().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that KVM no longer uses wired entries we can safely use
local_flush_tlb_all() when we need to flush the entire TLB (on the start
of a new ASID cycle). This doesn't flush wired entries, which allows
other code to use them without KVM clobbering them all the time. It also
is more up to date, knowing about the tlbinv architectural feature,
flushing of micro TLB on cores where that is necessary (Loongson I
believe), and knows to stop the HTW while doing so.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that we have GVA page tables, use standard user accesses with page
faults disabled to read & modify guest instructions. This should be more
robust (than the rather dodgy method of accessing guest mapped segments
by just directly addressing them) and will also work with Enhanced
Virtual Addressing (EVA) host kernel configurations where dedicated
instructions are needed for accessing user mode memory.
For simplicity and speed we do this regardless of the guest segment the
address resides in, rather than handling guest KSeg0 specially with
kmap_atomic() as before.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that the commpage doesn't use wired TLB entries, the per-CPU
vm_init() callback is the only work done by kvm_mips_init_vm_percpu().
The trap & emulate implementation doesn't actually need to do anything
from vm_init(), and the future VZ implementation would be better served
by a kvm_arch_hardware_enable callback anyway.
Therefore drop the vm_init() callback entirely, allowing the
kvm_mips_init_vm_percpu() function to also be dropped, along with the
kvm_mips_instance atomic counter.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that we have GVA page tables and an optimised TLB refill handler in
place, convert the handling of commpage faults from the guest kernel to
fill the GVA page table and invalidate the TLB entry, rather than
filling the wired TLB entry directly.
For simplicity we no longer use a wired entry for the commpage (refill
should be much cheaper with the fast-path handler anyway). Since we
don't need to manipulate the TLB directly any longer, move the function
from tlb.c to mmu.c. This puts it closer to the similar functions
handling KSeg0 and TLB mapped page faults from the guest.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Now that we have GVA page tables and an optimised TLB refill handler in
place, convert the handling of page faults in TLB mapped segment from
the guest to fill a single GVA page table entry and invalidate the TLB
entry, rather than filling a TLB entry pair directly.
Also remove the now unused kvm_mips_get_{kernel,user}_asid() functions
in mmu.c and kvm_mips_host_tlb_write() in tlb.c.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Implement invalidation of specific pairs of GVA page table entries in
one or both of the GVA page tables. This is used when existing mappings
are replaced in the guest TLB by emulated TLBWI/TLBWR instructions. Due
to the sharing of page tables in the host kernel range, we should be
careful not to allow host pages to be invalidated.
Add a helper kvm_mips_walk_pgd() which can be used when walking of
either GPA (future patches) or GVA page tables is needed, optionally
with allocation of page tables along the way when they don't exist.
GPA page table walking will need to be protected by the kvm->mmu_lock,
so we also add a small MMU page cache in each KVM VCPU, like that found
for other architectures but smaller. This allows enough pages to be
pre-allocated to handle a single fault without holding the lock,
allowing the helper to run with the lock held without having to handle
allocation failures.
Using the same mechanism for GVA allows the same code to be used, and
allows it to use the same cache of allocated pages if the GPA walk
didn't need to allocate any new tables.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Implement invalidation of large ranges of virtual addresses from GVA
page tables in response to a guest ASID change (immediately for guest
kernel page table, lazily for guest user page table).
We iterate through a range of page tables invalidating entries and
freeing fully invalidated tables. To minimise overhead the exact ranges
invalidated depends on the flags argument to kvm_mips_flush_gva_pt(),
which also allows it to be used in future KVM_CAP_SYNC_MMU patches in
response to GPA changes, which unlike guest TLB mapping changes affects
guest KSeg0 mappings.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Refactor kvm_mips_host_tlb_inv() to also be able to invalidate any
matching TLB entry in the kernel ASID rather than assuming only the TLB
entries in the user ASID can change. Two new bool user/kernel arguments
allow the caller to indicate whether the mapping should affect each of
the ASIDs for guest user/kernel mode.
- kvm_mips_invalidate_guest_tlb() (used by TLBWI/TLBWR emulation) can
now invalidate any corresponding TLB entry in both the kernel ASID
(guest kernel may have accessed any guest mapping), and the user ASID
if the entry being replaced is in guest USeg (where guest user may
also have accessed it).
- The tlbmod fault handler (and the KSeg0 / TLB mapped / commpage fault
handlers in later patches) can now invalidate the corresponding TLB
entry in whichever ASID is currently active, since only a single page
table will have been updated anyway.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Use functions from the general MIPS TLB exception vector generation code
(tlbex.c) to construct a fast path TLB refill handler similar to the
general one, but cut down and capable of preserving K0 and K1.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Activate the GVA page tables when in guest context. This will allow the
normal Linux TLB refill handler to fill from it when guest memory is
read, as well as preventing accidental reading from user memory.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Wire up a vcpu uninit implementation callback. This will be used for the
clean up of GVA->HPA page tables.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Set init_mm as the active_mm and update mm_cpumask(current->mm) to
reflect that it isn't active when in guest context. This prevents cache
management code from attempting cache flushes on host virtual addresses
while in guest context, for example due to a cache management IPIs or
later when writing of dynamically translated code hits copy on write.
We do this using helpers in static kernel code to avoid having to export
init_mm to modules.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add implementation callbacks for entering the guest (vcpu_run()) and
reentering the guest (vcpu_reenter()), allowing implementation specific
operations to be performed before entering the guest or after returning
to the host without cluttering kvm_arch_vcpu_ioctl_run().
This allows the T&E specific lazy user GVA flush to be moved into
trap_emul.c, along with disabling of the HTW. We also move
kvm_mips_deliver_interrupts() as VZ will need to restore the guest timer
state prior to delivering interrupts.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The kvm_vcpu_arch structure contains both mm_structs for allocating MMU
contexts (primarily the ASID) but it also copies the resulting ASIDs
into guest_{user,kernel}_asid[] arrays which are referenced from uasm
generated code.
This duplication doesn't seem to serve any purpose, and it gets in the
way of generalising the ASID handling across guest kernel/user modes, so
lets just extract the ASID straight out of the mm_struct on demand, and
in fact there are convenient cpu_context() and cpu_asid() macros for
doing so.
To reduce the verbosity of this code we do also add kern_mm and user_mm
local variables where the kernel and user mm_structs are used.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Convert the get_regs() and set_regs() callbacks to vcpu_load() and
vcpu_put(), which provide a cpu argument and more closely match the
kvm_arch_vcpu_load() / kvm_arch_vcpu_put() that they are called by.
This is in preparation for moving ASID management into the
implementations.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
KVM T&E uses an ASID for guest kernel mode and an ASID for guest user
mode. The current ASID is saved when the guest is scheduled out, and
restored when scheduling back in, with checks for whether the ASID needs
to be regenerated.
This isn't really necessary as the ASID can be easily determined by the
current guest mode, so lets simplify it to just read the required ASID
from guest_kernel_asid or guest_user_asid even if the ASID hasn't been
regenerated.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
The protected cache ops contain no out of line fixup code to return an
error code in the event of a fault, with the cache op being skipped in
that case. For KVM however we'd like to detect this case as page
faulting will be disabled so it could happen during normal operation if
the GVA page tables were flushed, and need to be handled by the caller.
Add the out-of-line fixup code to load the error value -EFAULT into the
return variable, and adapt the protected cache line functions to pass
the error back to the caller.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Export to TLB exception code generating functions so that KVM can
construct a fast TLB refill handler for guest context without
reinventing the wheel quite so much.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Add include guards in asm/uasm.h to allow it to be safely used by a new
header asm/tlbex.h in the next patch to expose TLB exception building
functions for KVM to use.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
pgd_alloc() references init_mm which is not exported to modules. In
order for KVM to be able to use pgd_alloc() to allocate GVA page tables,
move pgd_alloc() into a new pgtable.c file and export it to modules.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
cputime_t is now only used by two architectures:
* powerpc (when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y)
* s390
And since the core doesn't use it anymore, we don't need any arch support
from the others. So we can remove their stub implementations.
A final cleanup would be to provide an efficient pure arch
implementation of cputime_to_nsec() for s390 and powerpc and finally
remove include/linux/cputime.h .
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1485832191-26889-36-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So far only Luxul XWR-1750 router was supported. This adds a set of
other Luxul devices based on BCM47XX. It's a standard support for LEDs
and buttons.
Signed-off-by: Dan Haab <dhaab@luxul.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15106/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
vdso.h includes <spaces.h> implicitly after defining CONFIG_32BITS.
This defeats the override in mach-ip27/spaces.h, leading to
a build error that shows up in kernelci.org:
In file included from arch/mips/include/asm/mach-ip27/spaces.h:29:0,
from arch/mips/include/asm/page.h:12,
from arch/mips/vdso/vdso.h:26,
from arch/mips/vdso/gettimeofday.c:11:
arch/mips/include/asm/mach-generic/spaces.h:28:0: error: "CAC_BASE" redefined [-Werror]
#define CAC_BASE _AC(0x80000000, UL)
An earlier patch tried to make the second definition conditional,
but that patch had the #ifdef in the wrong place, and would lead
to another warning:
arch/mips/include/asm/io.h: In function 'phys_to_virt':
arch/mips/include/asm/io.h:138:9: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
For all I can tell, there is no other reason than vdso32 to ever
include this file with CONFIG_32BITS set, and the vdso itself should
never refer to the base addresses as it is running in user space,
so adding an #ifdef here is safe.
Link: https://patchwork.kernel.org/patch/9418187/
Fixes: 3ffc17d876 ("MIPS: Adjust MIPS64 CAC_BASE to reflect Config.K0")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15039/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
kernelci.org reports tons of build warnings for linux-next:
35 WARNING: "memcpy" [fs/fat/msdos.ko] has no CRC!
35 WARNING: "__copy_user" [fs/fat/fat.ko] has no CRC!
32 WARNING: EXPORT symbol "memset" [vmlinux] version generation failed, symbol will not be versioned.
32 WARNING: EXPORT symbol "copy_page" [vmlinux] version generation failed, symbol will not be versioned.
32 WARNING: EXPORT symbol "clear_page" [vmlinux] version generation failed, symbol will not be versioned.
32 WARNING: EXPORT symbol "__strncpy_from_user_nocheck_asm" [vmlinux] version generation failed, symbol will not be versioned.
The problem here is mainly the missing asm/asm-prototypes.h header file
that is supposed to include the prototypes for each symbol that is exported
from an assembler file.
A second problem is that the asm/uaccess.h header contains some but not
all the necessary declarations for the user access helpers.
Finally, the vdso build is broken once we add asm/asm-prototypes.h, so
we have to fix this at the same time by changing the vdso header. My
approach here is to just not look for exported symbols in the VDSO
assembler files, as the symbols cannot be exported anyway.
Fixes: 576a2f0c5c ("MIPS: Export memcpy & memset functions alongside their definitions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15038/
Patchwork: https://patchwork.linux-mips.org/patch/15069/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Introduce a new architecture-specific get_arch_dma_ops() function
that takes a struct bus_type * argument. Add get_dma_ops() in
<linux/dma-mapping.h>.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Russell King <linux@armlinux.org.uk>
Cc: x86@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
Some but not all architectures provide set_dma_ops(). Move dma_ops
from struct dev_archdata into struct device such that it becomes
possible on all architectures to configure dma_ops per device.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Russell King <linux@armlinux.org.uk>
Cc: x86@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
When building a kernel targeting a microMIPS ISA, recent GNU linkers
will fail the link if they cannot determine that the target of a branch
or jump is microMIPS code, with errors such as the following:
mips-img-linux-gnu-ld: arch/mips/built-in.o: .text+0x542c:
Unsupported jump between ISA modes; consider recompiling with
interlinking enabled.
mips-img-linux-gnu-ld: final link failed: Bad value
or:
./arch/mips/include/asm/uaccess.h:1017: warning: JALX to a
non-word-aligned address
Placing anything other than an instruction at the start of a function
written in assembly appears to trigger such errors. In order to prepare
for allowing us to follow function prologue macros with an EXPORT_SYMBOL
invocation, end the prologue macros (LEAD, NESTED & FEXPORT) with a
.insn directive. This ensures that the start of the function is marked
as code, which always makes sense for functions & safely prevents us
from hitting the link errors described above.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14508/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Include export.h in the list of generic headers used by the MIPS
architecture for use by later patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The mt7620 has a pin that can be used to generate an external reference
clock. The pinmux setup was missing the definition of said pin. This patch
adds it.
Signed-off-by: John Crispin <john@phrozen.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14898/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add plat_fdt_relocated(void*) API to allow the kernel relocation code to
update platform's information about the DTB location if the DTB had to
be moved due to being placed in a location used by the relocated kernel.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14611/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS does not currently define ELF_CORE_COPY_REGS macros and as a result
the generic implementation is used. The generic version attempts to do
directly map (struct pt_regs) into (elf_gregset_t), which isn't correct
for MIPS platforms and also triggers a BUG() at runtime in
include/linux/elfcore.h:16 (BUG_ON(sizeof(*elfregs) != sizeof(*regs)))
[ralf@linux-mips.org: Add semicolons to the macro definitions as I do not
apply https://patchwork.linux-mips.org/patch/14588/ for now.]
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14586/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Current register dump methods for MIPS are implemented inside ptrace
methods, but there will be other uses in the kernel for them, so keep
them separately in process.c and use those definitions for ptrace
instead.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14587/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
SMP_DUMP has been added as a new IPI signal when kexec support was added
for Cavium Octeon CPUs ('commit 7aa1c8f47e ("MIPS: kdump: Add support")'.
However, the new signal doesn't appear to ever have a proper handler
added (octeon_message_functions[] array has an empty handler for it),
and generic IPI handlers now trigger a BUG() on unhandled signal.
As the method is unused remove it completely and replace its only
invocation with a smp_call_function().
[ralf@linux-mips.org: Renumber SMP_ASK_C0COUNT to avoid numbering gaps.]
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14630/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 7c151d3d5d ("MIPS: Make use of the ERETNC instruction on MIPS
R6") began clearing LLBit during context switches, but did so on all
systems where it is writable for unclear reasons & did so from a macro
with "software_ll_bit" in its name, which is intended to operate on the
ll_bit variable used by ll/sc emulation for old CPUs.
We do now need to clear LLBit on MIPSr6 systems where we'll use eretnc
to return to userland, but we don't need to do so on MIPSr5 systems with
a writable LLBit.
Move the clear to its own appropriately named macro, do it only for
MIPSr6 systems & comment about why.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14409/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The r2_emul_return field in struct thread_info was used in order to take
an alternate codepath when returning to userland, which (besides not
implementing certain features) effectively used the eretnc instruction
in place of eret. The difference is that eretnc doesn't clear LLBit, and
therefore doesn't cause a linked load & store sequence to fail due to
emulation like eret would.
The reason eret would usually be used to clear LLBit is so that after
context switching we ensure that a load performed by one task doesn't
influence another task. However commit 7c151d3d5d ("MIPS: Make use of
the ERETNC instruction on MIPS R6") which introduced the r2_emul_return
field and conditional use of eretnc also for some reason began
explicitly clearing LLBit during context switches - despite retaining
the use of eret for everything but returns from the pre-r6 instruction
emulation code.
As LLBit is cleared upon context switches anyway, simplify this by using
eretnc unconditionally for MIPSr6 kernels. This allows us to remove the
4 byte r2_emul_return boolean from struct thread_info, simplify the
return to user code in entry.S and avoid the overhead of tracking &
checking state which we don't need.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
On systems with CM3, we must ensure that the L1 & L2 ECC enables are set
to the same value. This is presumed by the hardware & cache corruption
can occur when it is not the case. Support enabling & disabling the L2
ECC checking on CM3 systems where this is controlled via a GCR, and
ensure that it matches the state of L1 ECC checking. Remove I6400 from
the switch statement it will no longer hit, and which was incorrect
since the L2 ECC enable bit isn't in the CP0 ErrCtl register.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14413/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The previous commit made cpu_callin_map redundant, since it is no longer
used to signal secondary CPUs starting, or going offline. Remove it now.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Yang Shi <yang.shi@windriver.com>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14503/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We have a HIGHMEM_DEBUG macro defined in asm/highmem.h with a comment
stating that it should be removed for production, and no users... Kill
it.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14523/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS-specific asm/unaligned.h provides nothing that the generic
version doesn't - it simply uses MIPS-specific endianness macros in
place of generic ones & lacks support for
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS. Remove it & switch to using the
generic version to remove duplication.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14412/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch enables KASLR for Octeon systems. The SMP startup code is
such that the secondaries monitor the volatile variable
'octeon_processor_relocated_kernel_entry' for any non-zero value.
The 'plat_post_relocation hook' is used to set that value to the
kernel entry point of the relocated kernel. The secondary CPUs will
then jusmp to the new kernel, perform their initialization again
and begin waiting for the boot CPU to start them via the relocated
loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14669/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The SAVE_SOME macro is used to save the execution context on all
exceptions.
If an exception occurs while executing user code, the stack is switched
to the kernel's stack for the current task, and register $28 is switched
to point to the current_thread_info, which is at the bottom of the stack
region.
If the exception occurs while executing kernel code, the stack is left,
and this change ensures that register $28 is not updated. This is the
correct behaviour when the kernel can be executing on the separate irq
stack, because the thread_info will not be at the base of it.
With this change, register $28 is only switched to it's kernel
conventional usage of the currrent thread info pointer at the point at
which execution enters kernel space. Doing it on every exception was
redundant, but OK without an IRQ stack, but will be erroneous once that
is introduced.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14742/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
