23 Oct, 2015
1 commit
-
commit 53960059d56ecef67d4ddd546731623641a3d2d1 upstream.
If there is a DMA zone (usually 24bit = 16MB I believe), but no DMA32
zone, as is the case for some 32-bit kernels, then massage_gfp_flags()
will cause DMA memory allocated for devices with a 32..63-bit
coherent_dma_mask to fall back to using __GFP_DMA, even though there may
only be 32-bits of physical address available anyway.Correct that case to compare against a mask the size of phys_addr_t
instead of always using a 64-bit mask.Signed-off-by: James Hogan
Fixes: a2e715a86c6d ("MIPS: DMA: Fix computation of DMA flags from device's coherent_dma_mask.")
Cc: Ralf Baechle
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9610/
Signed-off-by: Ralf Baechle
Signed-off-by: Greg Kroah-Hartman
11 Aug, 2015
1 commit
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commit cccf34e9411c41b0cbfb41980fe55fc8e7c98fd2 upstream.
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
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10654/
Signed-off-by: Ralf Baechle
Signed-off-by: Greg Kroah-Hartman
06 Jun, 2015
1 commit
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Fixes a typo in arch/mips/mm/c-r4k.c's probe_scache().
Signed-off-by: Joshua Kinard
Signed-off-by: Ralf Baechle
16 May, 2015
1 commit
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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
Cc: David Daney
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10038/
Signed-off-by: Ralf Baechle
18 Apr, 2015
1 commit
-
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
...
15 Apr, 2015
2 commits
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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
Cc: Hector Marco-Gisbert
Cc: Russell King
Reviewed-by: Ingo Molnar
Cc: Catalin Marinas
Cc: Will Deacon
Cc: Ralf Baechle
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: Martin Schwidefsky
Cc: Heiko Carstens
Cc: Alexander Viro
Cc: Oleg Nesterov
Cc: Andy Lutomirski
Cc: "David A. Long"
Cc: Andrey Ryabinin
Cc: Arun Chandran
Cc: Yann Droneaud
Cc: Min-Hua Chen
Cc: Paul Burton
Cc: Alex Smith
Cc: Markos Chandras
Cc: Vineeth Vijayan
Cc: Jeff Bailey
Cc: Michael Holzheu
Cc: Ben Hutchings
Cc: Behan Webster
Cc: Ismael Ripoll
Cc: Jan-Simon Mller
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In preparation for splitting out ET_DYN ASLR, extract the mmap ASLR
selection into a separate function.Signed-off-by: Kees Cook
Reviewed-by: Ingo Molnar
Cc: Ralf Baechle
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Apr, 2015
1 commit
10 Apr, 2015
1 commit
-
For a discussion, see http://patchwork.linux-mips.org/patch/9539/.
This reverts commit 625c0a21700bdb90844d926a1508a17a77e369c9.
02 Apr, 2015
1 commit
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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
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8507/
Signed-off-by: Ralf Baechle
01 Apr, 2015
2 commits
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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
Cc: Linux MIPS List
Patchwork: https://patchwork.linux-mips.org/patch/9092/
Signed-off-by: Ralf Baechle -
Signed-off-by: Ralf Baechle
25 Mar, 2015
2 commits
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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
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 -
Revert commit 2a4a8b1e5d9d ("MIPS: Remove race window in page fault
handling") because it increased the number of flushed dcache pages and
became a performance problem for some workloads.Signed-off-by: Lars Persson
Cc: linux-mips@linux-mips.org
Cc: paul.burton@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9345/
Signed-off-by: Ralf Baechle
20 Mar, 2015
1 commit
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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
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9355/
Signed-off-by: Ralf Baechle
18 Mar, 2015
1 commit
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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
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9353/
Signed-off-by: Ralf Baechle
22 Feb, 2015
1 commit
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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
...
21 Feb, 2015
1 commit
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In commit c441d4a54c6e ("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
Reviewed-by: Maciej W. Rozycki
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Valentin Rothberg
Cc: Paul Bolle
Patchwork: https://patchwork.linux-mips.org/patch/9267/
Signed-off-by: Ralf Baechle
20 Feb, 2015
2 commits
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Make messages refer to all CN6XXX.
Signed-off-by: David Daney
Signed-off-by: Aleksey Makarov
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8941/
Signed-off-by: Ralf Baechle -
Build set and clear macros for the PageGrain register.
Signed-off-by: Steven J. Hill
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9289/
Signed-off-by: Ralf Baechle
17 Feb, 2015
4 commits
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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
-
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
-
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
Signed-off-by: Markos Chandras -
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
16 Feb, 2015
4 commits
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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
Signed-off-by: Markos Chandras -
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
Signed-off-by: Markos Chandras -
Add a CPU_QEMU_GENERIC case to various switch statements.
Signed-off-by: Leonid Yegoshin
Signed-off-by: Markos Chandras -
Commit 41c594ab65fc ("[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
Cc: James Hogan
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9089/
Signed-off-by: Ralf Baechle
12 Feb, 2015
2 commits
-
This allows the get_user_pages_fast slow path to release the mmap_sem
before blocking.Signed-off-by: Andrea Arcangeli
Reviewed-by: Kirill A. Shutemov
Cc: Andres Lagar-Cavilla
Cc: Peter Feiner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
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
Acked-by: Hugh Dickins
Cc: James Hogan
Cc: David Rientjes
Cc: Mel Gorman
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Rik van Riel
Cc: Andrea Arcangeli
Cc: Luiz Capitulino
Cc: Nishanth Aravamudan
Cc: Lee Schermerhorn
Cc: Steve Capper
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Feb, 2015
1 commit
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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).
...
31 Jan, 2015
1 commit
-
The following commits:
5890f70f15c52d (MIPS: Use dedicated exception handler if CPU supports RI/XI exceptions)
6575b1d4173eae (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
Cc:
Cc: Leonid Yegoshin
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/8880/
Signed-off-by: Ralf Baechle
30 Jan, 2015
1 commit
-
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 fee7e49d4514 ("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
Tested-by: Jan Engelhardt
Acked-by: Heiko Carstens # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds
21 Dec, 2014
1 commit
-
Pull ACCESS_ONCE cleanup preparation from Christian Borntraeger:
"kernel: Provide READ_ONCE and ASSIGN_ONCEAs discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com
ACCESS_ONCE might fail with specific compilers for non-scalar
accesses.Here is a set of patches to tackle that problem.
The first patch introduce READ_ONCE and ASSIGN_ONCE. If the data
structure is larger than the machine word size memcpy is used and a
warning is emitted. The next patches fix up several in-tree users of
ACCESS_ONCE on non-scalar types.This does not yet contain a patch that forces ACCESS_ONCE to work only
on scalar types. This is targetted for the next merge window as Linux
next already contains new offenders regarding ACCESS_ONCE vs.
non-scalar types"* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux:
s390/kvm: REPLACE barrier fixup with READ_ONCE
arm/spinlock: Replace ACCESS_ONCE with READ_ONCE
arm64/spinlock: Replace ACCESS_ONCE READ_ONCE
mips/gup: Replace ACCESS_ONCE with READ_ONCE
x86/gup: Replace ACCESS_ONCE with READ_ONCE
x86/spinlock: Replace ACCESS_ONCE with READ_ONCE
mm: replace ACCESS_ONCE with READ_ONCE or barriers
kernel: Provide READ_ONCE and ASSIGN_ONCE
18 Dec, 2014
1 commit
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ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)Change the gup code to replace ACCESS_ONCE with READ_ONCE.
Signed-off-by: Christian Borntraeger
Acked-by: Paul E. McKenney
12 Dec, 2014
1 commit
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Pull MIPS updates from Ralf Baechle:
"This is an unusually large pull request for MIPS - in parts because
lots of patches missed the 3.18 deadline but primarily because some
folks opened the flood gates.- Retire the MIPS-specific phys_t with the generic phys_addr_t.
- Improvments for the backtrace code used by oprofile.
- Better backtraces on SMP systems.
- Cleanups for the Octeon platform code.
- Cleanups and fixes for the Loongson platform code.
- Cleanups and fixes to the firmware library.
- Switch ATH79 platform to use the firmware library.
- Grand overhault to the SEAD3 and Malta interrupt code.
- Move the GIC interrupt code to drivers/irqchip
- Lots of GIC cleanups and updates to the GIC code to use modern IRQ
infrastructures and features of the kernel.
- OF documentation updates for the GIC bindings
- Move GIC clocksource driver to drivers/clocksource
- Merge GIC clocksource driver with clockevent driver.
- Further updates to bring the GIC clocksource driver up to date.
- R3000 TLB code cleanups
- Improvments to the Loongson 3 platform code.
- Convert pr_warning to pr_warn.
- Merge a bunch of small lantiq and ralink fixes that have been
staged/lingering inside the openwrt tree for a while.
- Update archhelp for IP22/IP32
- Fix a number of issues for Loongson 1B.
- New clocksource and clockevent driver for Loongson 1B.
- Further work on clk handling for Loongson 1B.
- Platform work for Broadcom BMIPS.
- Error handling cleanups for TurboChannel.
- Fixes and optimization to the microMIPS support.
- Option to disable the FTLB.
- Dump more relevant information on machine check exception
- Change binfmt to allow arch to examine PT_*PROC headers
- Support for new style FPU register model in O32
- VDSO randomization.
- BCM47xx cleanups
- BCM47xx reimplement the way the kernel accesses NVRAM information.
- Random cleanups
- Add support for ATH25 platforms
- Remove pointless locking code in some PCI platforms.
- Some improvments to EVA support
- Minor Alchemy cleanup"* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (185 commits)
MIPS: Add MFHC0 and MTHC0 instructions to uasm.
MIPS: Cosmetic cleanups of page table headers.
MIPS: Add CP0 macros for extended EntryLo registers
MIPS: Remove now unused definition of phys_t.
MIPS: Replace use of phys_t with phys_addr_t.
MIPS: Replace MIPS-specific 64BIT_PHYS_ADDR with generic PHYS_ADDR_T_64BIT
PCMCIA: Alchemy Don't select 64BIT_PHYS_ADDR in Kconfig.
MIPS: lib: memset: Clean up some MIPS{EL,EB} ifdefery
MIPS: iomap: Use __mem_{read,write}{b,w,l} for MMIO
MIPS: fix indentation.
MAINTAINERS: Add entry for BMIPS multiplatform kernel
MIPS: Enable VDSO randomization
MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration
MIPS: Remove declaration of obsolete arch_init_clk_ops()
MIPS: atomic.h: Reformat to fit in 79 columns
MIPS: Apply `.insn' to fixup labels throughout
MIPS: Fix microMIPS LL/SC immediate offsets
MIPS: Kconfig: Only allow 32-bit microMIPS builds
MIPS: signal.c: Fix an invalid cast in ISA mode bit handling
MIPS: mm: Only build one microassembler that is suitable
...
28 Nov, 2014
1 commit
-
There is a potential race when probing the TLB in TLBL/M/S exception
handlers for a matching entry. Between the time we hit a TLBL/S/M
exception and the time we get to execute the TLBP instruction, the
HTW may have replaced the TLB entry we are interested in hence the TLB
probe may fail. However, in the existing handlers, we never checked the
status of the TLBP (ie check the result in the C0/Index register). We
fix this by adding such a check when the core implements the HTW. If
we couldn't find a matching entry, we return back and try again.Signed-off-by: Leonid Yegoshin
Signed-off-by: Markos Chandras
Reviewed-by: James Hogan
Cc: # v3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8599/
Signed-off-by: Ralf Baechle
25 Nov, 2014
3 commits
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New instructions for Extended Physical Addressing (XPA) functionality.
Signed-off-by: Steven J. Hill
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8453/
Signed-off-by: Ralf Baechle -
Signed-off-by: Ralf Baechle
-
Signed-off-by: Ralf Baechle