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
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
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>
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>
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>
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>
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 $28 is only switched to it's kernel
conventional usage of the currrent thread info pointer at the point at
which execution enters kernel space. Doing it on every exception was
redundant, but OK without an IRQ stack, but will be erroneous once that
is introduced.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14742/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull RTC updates from Alexandre Belloni:
"Subsystem:
- non-modular drivers are now explicitly non-modular
New driver:
- Epson Toyocom rtc-7301sf/dg
Drivers:
- cmos: reject unsupported alarm values wrt the RTC capabilities
- ds1307: ACPI support
- jz4740: DT support, jz4780 handling, can now be used as a system
power controller
- mcp795: many fixes, in particular proper month handling
- twl: driver is now DT only"
* tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (31 commits)
rtc: mcp795: Fix whitespace and indentation.
rtc: mcp795: Prefer using the BIT() macro.
rtc: mcp795: fix month write resetting date to 1.
rtc: mcp795: fix time range difference between linux and RTC chip.
rtc: mcp795: fix bitmask value for leap year (LP).
rtc: mcp795: use bcd2bin/bin2bcd.
rtc: add support for EPSON TOYOCOM RTC-7301SF/DG
rtc: ds1307: Add ACPI support
rtc: imxdi: (trivial) fix a typo
rtc: ds1374: Merge conditional + WARN_ON()
rtc: twl: make driver DT only
rtc: twl: kill static variables
rtc: fix typos in Kconfig
rtc: jz4740: make the driver builtin only
rtc: jz4740: remove unused EXPORT_SYMBOL
Documentation: bindings: fix twl-rtc documentation
rtc: Enable compile testing for Maxim and Samsung drivers
MIPS: jz4740: Remove obsolete code
MIPS: qi_lb60: Probe RTC driver from DT and use it as power controller
MIPS: jz4740: DTS: Probe the jz4740-rtc driver from devicetree
...
Since MIPSr6 the Wired register is split into 2 fields, with the upper
16 bits of the register indicating a limit on the value that the wired
entry count in the bottom 16 bits of the register can take. This means
that simply reading the wired register doesn't get us a valid TLB entry
index any longer, and we instead need to retrieve only the lower 16 bits
of the register. Introduce a new num_wired_entries() function which does
this on MIPSr6 or higher and simply returns the value of the wired
register on older architecture revisions, and make use of it when
reading the number of wired entries.
Since commit e710d66683 ("MIPS: tlb-r4k: If there are wired entries,
don't use TLBINVF") we have been using a non-zero number of wired
entries to determine whether we should avoid use of the tlbinvf
instruction (which would invalidate wired entries) and instead loop over
TLB entries in local_flush_tlb_all(). This loop begins with the number
of wired entries, or before this patch some large bogus TLB index on
MIPSr6 systems. Thus since the aforementioned commit some MIPSr6 systems
with FTLBs have been prone to leaving stale address translations in the
FTLB & crashing in various weird & wonderful ways when we later observe
the wrong memory.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14557/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
