Execution of break instruction, trap instructions, emulation of unaligned
loads or floating point instructions - anything that tries to read the
instruction's opcode from userspace - needs read access to a page.
RIXI (Read Inhibit / Execute Inhibit) support however allows the creation of
pags that are executable but not readable. On such a mapping the attempted
load of the opcode by the kernel is going to cause an endless loop of
page faults.
The quick workaround for this is to disable the combinations that the kernel
currently isn't able to handle which are executable mappings.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The L2 cache in the I6400 core has 16 ways, so extend the way_string
array to take such caches into account.
[ralf@linux-mips.org: Other already supported CPUs are free to support
more than 8 ways of cache as well.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10640/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MT_SMP is not the only SMP option for MT cores. The MT_SMP option
allows more than one VPE per core to appear as a secondary CPU in the
system. Because of how CM works, it propagates the address-based
cache ops to the secondary cores but not the index-based ones.
Because of that, the code does not use IPIs to flush the L1 caches on
secondary cores because the CM would have done that already. However,
the CM functionality is independent of the type of SMP kernel so even in
non-MT kernels, IPIs are not necessary. As a result of which, we change
the conditional to depend on the CM presence. Moreover, since VPEs on
the same core share the same L1 caches, there is no need to send an
IPI on all of them so we calculate a suitable cpumask with only one
VPE per core.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10654/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
- Improvements to the tlb_dump code
- KVM fixes
- Add support for appended DTB
- Minor improvements to the R12000 support
- Minor improvements to the R12000 support
- Various platform improvments for BCM47xx
- The usual pile of minor cleanups
- A number of BPF fixes and improvments
- Some improvments to the support for R3000 and DECstations
- Some improvments to the ATH79 platform support
- A major patchset for the JZ4740 SOC adding support for the CI20 platform
- Add support for the Pistachio SOC
- Minor BMIPS/BCM63xx platform support improvments.
- Avoid "SYNC 0" as memory barrier when unlocking spinlocks
- Add support for the XWR-1750 board.
- Paul's __cpuinit/__cpuinitdata cleanups.
- New Malta CPU board support large memory so enable ZONE_DMA32.
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (131 commits)
MIPS: spinlock: Adjust arch_spin_lock back-off time
MIPS: asmmacro: Ensure 64-bit FP registers are used with MSA
MIPS: BCM47xx: Simplify handling SPROM revisions
MIPS: Cobalt Don't use module_init in non-modular MTD registration.
MIPS: BCM47xx: Move NVRAM driver to the drivers/firmware/
MIPS: use for_each_sg()
MIPS: BCM47xx: Don't select BCMA_HOST_PCI
MIPS: BCM47xx: Add helper variable for storing NVRAM length
MIPS: IRQ/IP27: Move IRQ allocation API to platform code.
MIPS: Replace smp_mb with release barrier function in unlocks.
MIPS: i8259: DT support
MIPS: Malta: Basic DT plumbing
MIPS: include errno.h for ENODEV in mips-cm.h
MIPS: Define GCR_GIC_STATUS register fields
MIPS: BPF: Introduce BPF ASM helpers
MIPS: BPF: Use BPF register names to describe the ABI
MIPS: BPF: Move register definition to the BPF header
MIPS: net: BPF: Replace RSIZE with SZREG
MIPS: BPF: Free up some callee-saved registers
MIPS: Xtalk: Update xwidget.h with known Xtalk device numbers
...
Currently we have many duplicates in definitions of huge_pmd_unshare. In
all architectures this function just returns 0 when
CONFIG_ARCH_WANT_HUGE_PMD_SHARE is N.
This patch puts the default implementation in mm/hugetlb.c and lets these
architectures use the common code.
Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Rientjes <rientjes@google.com>
Cc: James Yang <James.Yang@freescale.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull scheduler updates from Ingo Molnar:
"The main changes are:
- lockless wakeup support for futexes and IPC message queues
(Davidlohr Bueso, Peter Zijlstra)
- Replace spinlocks with atomics in thread_group_cputimer(), to
improve scalability (Jason Low)
- NUMA balancing improvements (Rik van Riel)
- SCHED_DEADLINE improvements (Wanpeng Li)
- clean up and reorganize preemption helpers (Frederic Weisbecker)
- decouple page fault disabling machinery from the preemption
counter, to improve debuggability and robustness (David
Hildenbrand)
- SCHED_DEADLINE documentation updates (Luca Abeni)
- topology CPU masks cleanups (Bartosz Golaszewski)
- /proc/sched_debug improvements (Srikar Dronamraju)"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits)
sched/deadline: Remove needless parameter in dl_runtime_exceeded()
sched: Remove superfluous resetting of the p->dl_throttled flag
sched/deadline: Drop duplicate init_sched_dl_class() declaration
sched/deadline: Reduce rq lock contention by eliminating locking of non-feasible target
sched/deadline: Make init_sched_dl_class() __init
sched/deadline: Optimize pull_dl_task()
sched/preempt: Add static_key() to preempt_notifiers
sched/preempt: Fix preempt notifiers documentation about hlist_del() within unsafe iteration
sched/stop_machine: Fix deadlock between multiple stop_two_cpus()
sched/debug: Add sum_sleep_runtime to /proc/<pid>/sched
sched/debug: Replace vruntime with wait_sum in /proc/sched_debug
sched/debug: Properly format runnable tasks in /proc/sched_debug
sched/numa: Only consider less busy nodes as numa balancing destinations
Revert 095bebf61a ("sched/numa: Do not move past the balance point if unbalanced")
sched/fair: Prevent throttling in early pick_next_task_fair()
preempt: Reorganize the notrace definitions a bit
preempt: Use preempt_schedule_context() as the official tracing preemption point
sched: Make preempt_schedule_context() function-tracing safe
x86: Remove cpu_sibling_mask() and cpu_core_mask()
x86: Replace cpu_**_mask() with topology_**_cpumask()
...
This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls. Since MIPS doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element. But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: akpm@linux-foundation.org
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9930/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit c5b367835c ("MIPS: Add support for XPA.") added generation of a
shift by _PAGE_PRESENT_SHIFT in build_pte_present() and
build_pte_writable(), however except for the XPA case this is always
zero making it unnecessary.
Make the shift conditional upon _PAGE_PRESENT_SHIFT being non-zero to
save an instruction in those cases.
Fixes: c5b367835c ("MIPS: Add support for XPA.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9889/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit c5b367835c ("MIPS: Add support for XPA.") changed
build_pte_present() and build_pte_writable() to assume a constant offset
of _PAGE_READ and _PAGE_WRITE relative to _PAGE_PRESENT, however this is
no longer true for some MIPS32R2 builds since commit be0c37c985
("MIPS: Rearrange PTE bits into fixed positions.") which moved the
_PAGE_READ PTE bit away from the _PAGE_PRESENT bit, with the _PAGE_WRITE
bit falling into its place.
Make use of the _PAGE_READ and _PAGE_WRITE definitions to calculate the
correct mask to apply instead of hard coding 3 (for _PAGE_PRESENT |
_PAGE_READ) or 5 (for _PAGE_PRESENT | _PAGE_WRITE).
Fixes: c5b367835c ("MIPS: Add support for XPA.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9888/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We removed __cpuinit support (leaving no-op stubs) quite some time ago.
However a new instance was added in commit c5b367835c
("MIPS: Add support for XPA.")
Since we want to clobber the stubs soon, get this removed now.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9894/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We removed __cpuinit support (leaving no-op stubs) quite some time ago.
However a new instance was added in commit 4caa906ee9
("MIPS: mm: c-r4k: Build EVA {d,i}cache flushing functions")
Since we want to clobber the stubs soon, get this removed now.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9893/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We removed __cpuinit support (leaving no-op stubs) quite some time ago.
However a few more crept in as of commit 6ee1d93455
("MIPS: BCM47XX: Detect more then 128 MiB of RAM (HIGHMEM)")
Since we want to clobber the stubs soon, get this removed now.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9892/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Replace an explicit barrier with a useful processor instruction in TLB
invalidation, following several other such cases elsewhere in
`tlb-r3k.c'.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10196/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move the initialisation of the CP0.Wired register implemented by Toshiba
TX3922 and TX3927 processors from `tx39_cache_init' to `tlb_init' where
it belongs, correcting code structure and making sure initialisation
does not rely on `tx39_cache_init' being called before `tlb_init' to
work correctly.
Make `r3k_have_wired_reg' static as it's no longer externally referred
to; remove a stale declaration too.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10195/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Most R3k processor implementations have their 8 first TLB entries fixed
as wired, so we always skip them in TLB invalidation. That however
means any leftover entries present there at boot will stay throughout
the life of the kernel, unless replaced with new ones.
So rename `local_flush_tlb_all' to `local_flush_tlb_from' and make it
accept the TLB entry to start from. Then use 0 initially at bootstrap,
and the first regular entry later on, bypassing any wired entries.
Wrap the latter arrangement into a new `local_flush_tlb_all' entry
point.
There is no need to disable interrupts in the call made from `tlb_init'
because it's made before the interrupt subsystem has been initialised;
this is also true for secondary processors, should we ever support R3k
SMP. So move this piece of code to new `local_flush_tlb_all'.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10194/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).
In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().
Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.
faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.
This patch is based on a patch from Thomas Gleixner.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The ELPA bit in PageGrain is all about large *physical* addresses, so
correct the reference to "large virtual address" in the comment above
where it is set for MIPS64.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10038/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for MIPS for Linux 4.1. Most
noteworthy:
- Add more Octeon-optimized crypto functions
- Octeon crypto preemption and locking fixes
- Little endian support for Octeon
- Use correct CSR to soft reset Octeons
- Support LEDs on the Octeon-based DSR-1000N
- Fix PCI interrupt mapping for the Octeon-based DSR-1000N
- Mark prom_free_prom_memory() as __init for a number of systems
- Support for Imagination's Pistachio SOC. This includes arch and
CLK bits. I'd like to merge pinctrl bits later
- Improve parallelism of csum_partial for certain pipelines
- Organize DTB files in subdirs like other architectures
- Implement read_sched_clock for all MIPS platforms other than
Octeon
- Massive series of 38 fixes and cleanups for the FPU emulator /
kernel
- Further FPU remulator work to support new features. This sits on a
separate branch which also has been pulled into the 4.1 KVM branch
- Clean up and fixes for the SEAD3 eval board; remove unused file
- Various updates for Netlogic platforms
- A number of small updates for Loongson 3 platforms
- Increase the memory limit for ATH79 platforms to 256MB
- A fair number of fixes and updates for BCM47xx platforms
- Finish the implementation of XPA support
- MIPS FDC support. No, not floppy controller but Fast Debug Channel :)
- Detect the R16000 used in SGI legacy platforms
- Fix Kconfig dependencies for the SSB bus support"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (265 commits)
MIPS: Makefile: Fix MIPS ASE detection code
MIPS: asm: elf: Set O32 default FPU flags
MIPS: BCM47XX: Fix detecting Microsoft MN-700 & Asus WL500G
MIPS: Kconfig: Disable SMP/CPS for 64-bit
MIPS: Hibernate: flush TLB entries earlier
MIPS: smp-cps: cpu_set FPU mask if FPU present
MIPS: lose_fpu(): Disable FPU when MSA enabled
MIPS: ralink: add missing symbol for RALINK_ILL_ACC
MIPS: ralink: Fix bad config symbol in PCI makefile.
SSB: fix Kconfig dependencies
MIPS: Malta: Detect and fix bad memsize values
Revert "MIPS: Avoid pipeline stalls on some MIPS32R2 cores."
MIPS: Octeon: Delete override of cpu_has_mips_r2_exec_hazard.
MIPS: Fix cpu_has_mips_r2_exec_hazard.
MIPS: kernel: entry.S: Set correct ISA level for mips_ihb
MIPS: asm: spinlock: Fix addiu instruction for R10000_LLSC_WAR case
MIPS: r4kcache: Use correct base register for MIPS R6 cache flushes
MIPS: Kconfig: Fix typo for the r2-to-r6 emulator kernel parameter
MIPS: unaligned: Fix regular load/store instruction emulation for EVA
MIPS: unaligned: Surround load/store macros in do {} while statements
...
When an architecture fully supports randomizing the ELF load location,
a per-arch mmap_rnd() function is used to find a randomized mmap base.
In preparation for randomizing the location of ET_DYN binaries
separately from mmap, this renames and exports these functions as
arch_mmap_rnd(). Additionally introduces CONFIG_ARCH_HAS_ELF_RANDOMIZE
for describing this feature on architectures that support it
(which is a superset of ARCH_BINFMT_ELF_RANDOMIZE_PIE, since s390
already supports a separated ET_DYN ASLR from mmap ASLR without the
ARCH_BINFMT_ELF_RANDOMIZE_PIE logic).
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Hector Marco-Gisbert <hecmargi@upv.es>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Arun Chandran <achandran@mvista.com>
Cc: Yann Droneaud <ydroneaud@opteya.com>
Cc: Min-Hua Chen <orca.chen@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Vineeth Vijayan <vvijayan@mvista.com>
Cc: Jeff Bailey <jeffbailey@google.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Behan Webster <behanw@converseincode.com>
Cc: Ismael Ripoll <iripoll@upv.es>
Cc: Jan-Simon Mller <dl9pf@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In preparation for splitting out ET_DYN ASLR, extract the mmap ASLR
selection into a separate function.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the 74K D-cache alias erratum workaround so that it actually works.
Our current code sets MIPS_CACHE_VTAG for the D-cache, but that flag
only has any effect for the I-cache. Additionally MIPS_CACHE_PINDEX is
set for the D-cache if CP0.Config7.AR is also set for an affected
processor, leading to confusing information in the bootstrap log (the
flag isn't used beyond that).
So delete the setting of MIPS_CACHE_VTAG and rely on MIPS_CACHE_ALIASES,
set in a common place, removing I-cache coherency issues seen in GDB
testing with software breakpoints, gdbserver and ptrace(2), on affected
systems.
While at it add a little piece of explanation of what CP0.Config6.SYND
is so that people do not have to chase documentation.
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8507/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This allows the kernel to correctly detect an R16000 MIPS CPU on systems that
have those. Otherwise, such systems will detect the CPU as an R14000, due to
similarities in the CPU PRId value.
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Cc: Linux MIPS List <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/9092/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The lazy cache flushing implemented in the MIPS kernel suffers from a
race condition that is exposed by do_set_pte() in mm/memory.c.
A pre-condition is a file-system that writes to the page from the CPU
in its readpage method and then calls flush_dcache_page(). One example
is ubifs. Another pre-condition is that the dcache flush is postponed
in __flush_dcache_page().
Upon a page fault for an executable mapping not existing in the
page-cache, the following will happen:
1. Write to the page
2. flush_dcache_page
3. flush_icache_page
4. set_pte_at
5. update_mmu_cache (commits the flush of a dcache-dirty page)
Between steps 4 and 5 another thread can hit the same page and it will
encounter a valid pte. Because the data still is in the L1 dcache the CPU
will fetch stale data from L2 into the icache and execute garbage.
This fix moves the commit of the cache flush to step 3 to close the
race window. It also reduces the amount of flushes on non-executable
mappings because we never enter __flush_dcache_page() for non-aliasing
CPUs.
Regressions can occur in drivers that mistakenly relies on the
flush_dcache_page() in get_user_pages() for DMA operations.
[ralf@linux-mips.org: Folded in patch 9346 to fix highmem issue.]
Signed-off-by: Lars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Cc: paul.burton@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9346/
Patchwork: https://patchwork.linux-mips.org/patch/9738/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add support for extended physical addressing (XPA) so that
32-bit platforms can access equal to or greater than 40 bits
of physical addresses.
NOTE:
1) XPA and EVA are not the same and cannot be used
simultaneously.
2) If you configure your kernel for XPA, the PTEs
and all address sizes become 64-bit.
3) Your platform MUST have working HIGHMEM support.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch rearranges the PTE bits into fixed positions for R2
and later cores. In the past, the TLB handling code did runtime
checking of RI/XI and adjusted the shifts and rotates in order
to fit the largest PFN value into the PTE. The checking now
occurs when building the TLB handler, thus eliminating those
checks. These new arrangements also define the largest possible
PFN value that can fit in the PTE. HUGE page support is only
available for 64-bit cores. Layouts of the PTE bits are now:
64-bit, R1 or earlier: CCC D V G [S H] M A W R P
32-bit, R1 or earler: CCC D V G M A W R P
64-bit, R2 or later: CCC D V G RI/R XI [S H] M A W P
32-bit, R2 or later: CCC D V G RI/R XI M A W P
[ralf@linux-mips.org: Fix another build error *rant* *rant*]
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9353/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for MIPS:
- a number of fixes that didn't make the 3.19 release.
- a number of cleanups.
- preliminary support for Cavium's Octeon 3 SOCs which feature up to
48 MIPS64 R3 cores with FPU and hardware virtualization.
- support for MIPS R6 processors.
Revision 6 of the MIPS architecture is a major revision of the MIPS
architecture which does away with many of original sins of the
architecture such as branch delay slots. This and other changes in
R6 require major changes throughout the entire MIPS core
architecture code and make up for the lion share of this pull
request.
- finally some preparatory work for eXtendend Physical Address
support, which allows support of up to 40 bit of physical address
space on 32 bit processors"
[ Ahh, MIPS can't leave the PAE brain damage alone. It's like
every CPU architect has to make that mistake, but pee in the snow
by changing the TLA. But whether it's called PAE, LPAE or XPA,
it's horrid crud - Linus ]
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
MIPS: sead3: Corrected get_c0_perfcount_int
MIPS: mm: Remove dead macro definitions
MIPS: OCTEON: irq: add CIB and other fixes
MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
MIPS: OCTEON: More OCTEONIII support
MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
MIPS: OCTEON: Update octeon-model.h code for new SoCs.
MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
MIPS: OCTEON: Implement the core-16057 workaround
MIPS: OCTEON: Delete unused COP2 saving code
MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
MIPS: OCTEON: Save and restore CP2 SHA3 state
MIPS: OCTEON: Fix FP context save.
MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
MIPS: boot: Provide more uImage options
MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
MIPS: ip22-gio: Remove legacy suspend/resume support
mips: pci: Add ifdef around pci_proc_domain
...
In commit c441d4a54c ("MIPS: mm: Only build one microassembler that
is suitable"), the Makefile at arch/mips/mm was rewritten to only
build the "right" microassembler file, depending on whether
CONFIG_CPU_MICROMIPS is set or not.
In the files, however, there are still preprocessor definitions
depending on CONFIG_CPU_MICROMIPS. The #ifdef around them can now
never evaluate to true, so let's remove them altogether.
This inconsistency was found using the undertaker-checkpatch tool.
Signed-off-by: Andreas Ruprecht <rupran@einserver.de>
Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Patchwork: https://patchwork.linux-mips.org/patch/9267/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The secondary cache initialization and configuration code is processor
specific so we need to handle MIPS R6 cores as well.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
The local_r4k_flush_cache_sigtramp function uses the 'cache'
instruction inside an asm block. However, MIPS R6 changed the
opcode for the cache instruction and as a result of which we
need to set the correct ISA level.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS uses the cpu_has_mips_r2_exec_hazard macro to determine whether the
EHB instruction is available or not. This is necessary for MIPS R6
which also supports the EHB instruction.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
The MIPS R6 pref instruction only has 9 bits for the immediate
field so skip the micro-assembler PREF instruction if the offset
does not fit in 9 bits. Moreover, bit 30 (Pref_PrepareForStore) is
no longer valid in MIPS R6, so we change the default for all MIPS R6
processors to bit 5 (Pref_StoreStreamed).
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS R6 defines new opcodes for ll, sc, cache and pref instructions
so we need to take these into consideration in the micro-assembler.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS R6 redefines several instructions and reduces the immediate
field to 9-bits so add related macros for the microassembler.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Add a CPU_QEMU_GENERIC case to various switch statements.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Commit 41c594ab65 ("[MIPS] MT: Improved multithreading support.")
removed useful debug information for userland segmentation faults.
This patch bring this back along with the ability to determine the
name of the object file where the EPC and RA registers point at.
Furthermore, we select the SYSCTL_EXCEPTION_TRACE symbol for MIPS
which is the de facto solution to turn userland exception logging
on and off via the /proc/sys/debug/exception-trace file.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9089/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This allows the get_user_pages_fast slow path to release the mmap_sem
before blocking.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we have many duplicates in definitions around
follow_huge_addr(), follow_huge_pmd(), and follow_huge_pud(), so this
patch tries to remove the m. The basic idea is to put the default
implementation for these functions in mm/hugetlb.c as weak symbols
(regardless of CONFIG_ARCH_WANT_GENERAL_HUGETL B), and to implement
arch-specific code only when the arch needs it.
For follow_huge_addr(), only powerpc and ia64 have their own
implementation, and in all other architectures this function just returns
ERR_PTR(-EINVAL). So this patch sets returning ERR_PTR(-EINVAL) as
default.
As for follow_huge_(pmd|pud)(), if (pmd|pud)_huge() is implemented to
always return 0 in your architecture (like in ia64 or sparc,) it's never
called (the callsite is optimized away) no matter how implemented it is.
So in such architectures, we don't need arch-specific implementation.
In some architecture (like mips, s390 and tile,) their current
arch-specific follow_huge_(pmd|pud)() are effectively identical with the
common code, so this patch lets these architecture use the common code.
One exception is metag, where pmd_huge() could return non-zero but it
expects follow_huge_pmd() to always return NULL. This means that we need
arch-specific implementation which returns NULL. This behavior looks
strange to me (because non-zero pmd_huge() implies that the architecture
supports PMD-based hugepage, so follow_huge_pmd() can/should return some
relevant value,) but that's beyond this cleanup patch, so let's keep it.
Justification of non-trivial changes:
- in s390, follow_huge_pmd() checks !MACHINE_HAS_HPAGE at first, and this
patch removes the check. This is OK because we can assume MACHINE_HAS_HPAGE
is true when follow_huge_pmd() can be called (note that pmd_huge() has
the same check and always returns 0 for !MACHINE_HAS_HPAGE.)
- in s390 and mips, we use HPAGE_MASK instead of PMD_MASK as done in common
code. This patch forces these archs use PMD_MASK, but it's OK because
they are identical in both archs.
In s390, both of HPAGE_SHIFT and PMD_SHIFT are 20.
In mips, HPAGE_SHIFT is defined as (PAGE_SHIFT + PAGE_SHIFT - 3) and
PMD_SHIFT is define as (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3), but
PTE_ORDER is always 0, so these are identical.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull MIPS fixes from Ralf Baechle:
"The pending MIPS fixes for 3.19. All across the field and nothing
particularly severe or dramatic"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (23 commits)
IRQCHIP: mips-gic: Avoid rerouting timer IRQs for smp-cmp
MIPS: Fix syscall_get_nr for the syscall exit tracing.
MIPS: elf2ecoff: Ignore PT_MIPS_ABIFLAGS program headers.
MIPS: elf2ecoff: Rewrite main processing loop to switch.
MIPS: fork: Fix MSA/FPU/DSP context duplication race
MIPS: Fix C0_Pagegrain[IEC] support.
MIPS: traps: Fix inline asm ctc1 missing .set hardfloat
MIPS: mipsregs.h: Add write_32bit_cp1_register()
MIPS: Fix kernel lockup or crash after CPU offline/online
MIPS: OCTEON: fix kernel crash when offlining a CPU
MIPS: ARC: Fix build error.
MIPS: IRQ: Fix disable_irq on CPU IRQs
MIPS: smp-mt,smp-cmp: Enable all HW IRQs on secondary CPUs
MIPS: Fix restart of indirect syscalls
MIPS: ELF: fix loading o32 binaries on 64-bit kernels
MIPS: mips-cm: Fix sparse warnings
MIPS: Kconfig: Fix recursive dependency.
MIPS: Compat: Fix build error if CONFIG_MIPS32_COMPAT but no compat ABI.
MIPS: JZ4740: Fixup #include's (sparse)
MIPS: Wire up execveat(2).
...
The following commits:
5890f70f15 (MIPS: Use dedicated exception handler if CPU supports RI/XI exceptions)
6575b1d417 (MIPS: kernel: cpu-probe: Detect unique RI/XI exceptions)
break the kernel for *all* existing MIPS CPUs that implement the
CP0_PageGrain[IEC] bit. They cause the TLB exception handlers to be
generated without the legacy execute-inhibit handling, but never set
the CP0_PageGrain[IEC] bit to activate the use of dedicated exception
vectors for execute-inhibit exceptions. The result is that upon
detection of an execute-inhibit violation, we loop forever in the TLB
exception handlers instead of sending SIGSEGV to the task.
If we are generating TLB exception handlers expecting separate
vectors, we must also enable the CP0_PageGrain[IEC] feature.
The bug was introduced in kernel version 3.17.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: <stable@vger.kernel.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/8880/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d45 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>