kernel.git/arch/mips/mm, branch linux-5.3.y

MIPS: tlbex: Fix build_restore_pagemask KScratch restore

2019-10-29T08:22:12Z

commit b42aa3fd5957e4daf4b69129e5ce752a2a53e7d6 upstream. build_restore_pagemask() will restore the value of register $1/$at when its restore_scratch argument is non-zero, and aims to do so by filling a branch delay slot. Commit 0b24cae4d535 ("MIPS: Add missing EHB in mtc0 -> mfc0 sequence.") added an EHB instruction (Execution Hazard Barrier) prior to restoring $1 from a KScratch register, in order to resolve a hazard that can result in stale values of the KScratch register being observed. In particular, P-class CPUs from MIPS with out of order execution pipelines such as the P5600 & P6600 are affected. Unfortunately this EHB instruction was inserted in the branch delay slot causing the MFC0 instruction which performs the restoration to no longer execute along with the branch. The result is that the $1 register isn't actually restored, ie. the TLB refill exception handler clobbers it - which is exactly the problem the EHB is meant to avoid for the P-class CPUs. Similarly build_get_pgd_vmalloc() will restore the value of $1/$at when its mode argument equals refill_scratch, and suffers from the same problem. Fix this by in both cases moving the EHB earlier in the emitted code. There's no reason it needs to immediately precede the MFC0 - it simply needs to be between the MTC0 & MFC0. This bug only affects Cavium Octeon systems which use build_fast_tlb_refill_handler(). Signed-off-by: Paul Burton Fixes: 0b24cae4d535 ("MIPS: Add missing EHB in mtc0 -> mfc0 sequence.") Cc: Dmitry Korotin Cc: stable@vger.kernel.org # v3.15+ Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

mips: properly account for stack randomization and stack guard gap

2019-10-07T17:01:45Z

[ Upstream commit b1f61b5bde3a1f50392c97b4c8513d1b8efb1cf2 ] This commit takes care of stack randomization and stack guard gap when computing mmap base address and checks if the task asked for randomization. This fixes the problem uncovered and not fixed for arm here: https://lkml.kernel.org/r/20170622200033.25714-1-riel@redhat.com Link: http://lkml.kernel.org/r/20190730055113.23635-10-alex@ghiti.fr Signed-off-by: Alexandre Ghiti Acked-by: Kees Cook Acked-by: Paul Burton Reviewed-by: Luis Chamberlain Cc: Albert Ou Cc: Alexander Viro Cc: Catalin Marinas Cc: Christoph Hellwig Cc: Christoph Hellwig Cc: James Hogan Cc: Palmer Dabbelt Cc: Ralf Baechle Cc: Russell King Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

MIPS: tlbex: Explicitly cast _PAGE_NO_EXEC to a boolean

2019-10-07T17:01:29Z

[ Upstream commit c59ae0a1055127dd3828a88e111a0db59b254104 ] clang warns: arch/mips/mm/tlbex.c:634:19: error: use of logical '&&' with constant operand [-Werror,-Wconstant-logical-operand] if (cpu_has_rixi && _PAGE_NO_EXEC) { ^ ~~~~~~~~~~~~~ arch/mips/mm/tlbex.c:634:19: note: use '&' for a bitwise operation if (cpu_has_rixi && _PAGE_NO_EXEC) { ^~ & arch/mips/mm/tlbex.c:634:19: note: remove constant to silence this warning if (cpu_has_rixi && _PAGE_NO_EXEC) { ~^~~~~~~~~~~~~~~~ 1 error generated. Explicitly cast this value to a boolean so that clang understands we intend for this to be a non-zero value. Fixes: 00bf1c691d08 ("MIPS: tlbex: Avoid placing software PTE bits in Entry* PFN fields") Link: https://github.com/ClangBuiltLinux/linux/issues/609 Signed-off-by: Nathan Chancellor Signed-off-by: Paul Burton Cc: Ralf Baechle Cc: James Hogan Cc: Nick Desaulniers Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: clang-built-linux@googlegroups.com Signed-off-by: Sasha Levin

Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping

2019-07-12T22:13:55Z

Pull dma-mapping updates from Christoph Hellwig: - move the USB special case that bounced DMA through a device bar into the USB code instead of handling it in the common DMA code (Laurentiu Tudor and Fredrik Noring) - don't dip into the global CMA pool for single page allocations (Nicolin Chen) - fix a crash when allocating memory for the atomic pool failed during boot (Florian Fainelli) - move support for MIPS-style uncached segments to the common code and use that for MIPS and nios2 (me) - make support for DMA_ATTR_NON_CONSISTENT and DMA_ATTR_NO_KERNEL_MAPPING generic (me) - convert nds32 to the generic remapping allocator (me) * tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits) dma-mapping: mark dma_alloc_need_uncached as __always_inline MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms usb: host: Fix excessive alignment restriction for local memory allocations lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators nios2: use the generic uncached segment support in dma-direct nds32: use the generic remapping allocator for coherent DMA allocations arc: use the generic remapping allocator for coherent DMA allocations dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code dma-mapping: add a dma_alloc_need_uncached helper openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support arc: remove the partial DMA_ATTR_NON_CONSISTENT support arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support ARM: dma-mapping: allow larger DMA mask than supported dma-mapping: truncate dma masks to what dma_addr_t can hold iommu/dma: Apply dma_{alloc,free}_contiguous functions dma-remap: Avoid de-referencing NULL atomic_pool MIPS: use the generic uncached segment support in dma-direct dma-direct: provide generic support for uncached kernel segments au1100fb: fix DMA API abuse ...

MIPS: use the generic get_user_pages_fast code

2019-07-12T18:05:44Z

The mips code is mostly equivalent to the generic one, minus various bugfixes and an arch override for gup_fast_permitted. Note that this defines ARCH_HAS_PTE_SPECIAL for mips as mips has pte_special and pte_mkspecial implemented and used in the existing gup code. They are no-op stubs, though which makes me a little unsure if this is really right thing to do. Note that this also adds back a missing cpu_has_dc_aliases check for __get_user_pages_fast, which the old code was only doing for get_user_pages_fast. This clearly looks like an oversight, as any condition that makes get_user_pages_fast unsafe also applies to __get_user_pages_fast. [hch@lst.de: MIPS: don't select ARCH_HAS_PTE_SPECIAL] Link: http://lkml.kernel.org/r/20190701151818.32227-3-hch@lst.de Link: http://lkml.kernel.org/r/20190625143715.1689-5-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Tested-by: Guenter Roeck Cc: Ralf Baechle Cc: Andrey Konovalov Cc: Benjamin Herrenschmidt Cc: David Miller Cc: James Hogan Cc: Khalid Aziz Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Paul Burton Cc: Paul Mackerras Cc: Rich Felker Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2019-07-09T04:48:15Z

Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...

MIPS: Add missing EHB in mtc0 -> mfc0 sequence.

2019-06-24T20:43:12Z

Add a missing EHB (Execution Hazard Barrier) in mtc0 -> mfc0 sequence. Without this execution hazard barrier it's possible for the value read back from the KScratch register to be the value from before the mtc0. Reproducible on P5600 & P6600. The hazard is documented in the MIPS Architecture Reference Manual Vol. III: MIPS32/microMIPS32 Privileged Resource Architecture (MD00088), rev 6.03 table 8.1 which includes: Producer | Consumer | Hazard ----------|----------|---------------------------- mtc0 | mfc0 | any coprocessor 0 register Signed-off-by: Dmitry Korotin [paul.burton@mips.com: - Commit message tweaks. - Add Fixes tags. - Mark for stable back to v3.15 where P5600 support was introduced.] Signed-off-by: Paul Burton Fixes: 3d8bfdd03072 ("MIPS: Use C0_KScratch (if present) to hold PGD pointer.") Fixes: 829dcc0a956a ("MIPS: Add MIPS P5600 probe support") Cc: linux-mips@vger.kernel.org Cc: stable@vger.kernel.org # v3.15+

MIPS: Fix bounds check virt_addr_valid

2019-06-16T22:51:22Z

The bounds check used the uninitialized variable vaddr, it should use the given parameter kaddr instead. When using the uninitialized value the compiler assumed it to be 0 and optimized this function to just return 0 in all cases. This should make the function check the range of the given address and only do the page map check in case it is in the expected range of virtual addresses. Fixes: 074a1e1167af ("MIPS: Bounds check virt_addr_valid") Cc: stable@vger.kernel.org # v4.12+ Cc: Paul Burton Signed-off-by: Hauke Mehrtens Signed-off-by: Paul Burton Cc: ralf@linux-mips.org Cc: jhogan@kernel.org Cc: f4bug@amsat.org Cc: linux-mips@vger.kernel.org Cc: ysu@wavecomp.com Cc: jcristau@debian.org

Merge tag 'mips_fixes_5.2_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

2019-06-08T20:09:31Z

Pull MIPS fixes from Paul Burton: - Declare ginvt() __always_inline due to its use of an argument as an inline asm immediate. - A VDSO build fix following Kbuild changes made this cycle. - A fix for boot failures on txx9 systems following memory initialization changes made this cycle. - Bounds check virt_addr_valid() to prevent it spuriously indicating that bogus addresses are valid, in turn fixing hardened usercopy failures that have been present since v4.12. - Build uImage.gz for pistachio systems by default, since this is the image we need in order to actually boot on a board. - Remove an unused variable in our uprobes code. * tag 'mips_fixes_5.2_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: MIPS: uprobes: remove set but not used variable 'epc' MIPS: pistachio: Build uImage.gz by default MIPS: Make virt_addr_valid() return bool MIPS: Bounds check virt_addr_valid MIPS: TXx9: Fix boot crash in free_initmem() MIPS: remove a space after -I to cope with header search paths for VDSO MIPS: mark ginvt() as __always_inline

MIPS: use the generic uncached segment support in dma-direct

2019-06-03T14:00:08Z

Stop providing the arch alloc/free hooks and just expose the segment offset instead. Signed-off-by: Christoph Hellwig Acked-by: Paul Burton