kernel.git/arch/mips/mm, branch linux-4.18.y

MIPS: WARN_ON invalid DMA cache maintenance, not BUG_ON

2018-09-19T20:41:37Z

[ Upstream commit d4da0e97baea8768b3d66ccef3967bebd50dfc3b ] If a driver causes DMA cache maintenance with a zero length then we currently BUG and kill the kernel. As this is a scenario that we may well be able to recover from, WARN & return in the condition instead. Signed-off-by: Paul Burton Acked-by: Florian Fainelli Patchwork: https://patchwork.linux-mips.org/patch/14623/ Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

MIPS: Fix ioremap() RAM check

2018-07-05T21:43:21Z

We currently attempt to check whether a physical address range provided to __ioremap() may be in use by the page allocator by examining the value of PageReserved for each page in the region - lowmem pages not marked reserved are presumed to be in use by the page allocator, and requests to ioremap them fail. The way we check this has been broken since commit 92923ca3aace ("mm: meminit: only set page reserved in the memblock region"), because memblock will typically not have any knowledge of non-RAM pages and therefore those pages will not have the PageReserved flag set. Thus when we attempt to ioremap a region outside of RAM we incorrectly fail believing that the region is RAM that may be in use. In most cases ioremap() on MIPS will take a fast-path to use the unmapped kseg1 or xkphys virtual address spaces and never hit this path, so the only way to hit it is for a MIPS32 system to attempt to ioremap() an address range in lowmem with flags other than _CACHE_UNCACHED. Perhaps the most straightforward way to do this is using ioremap_uncached_accelerated(), which is how the problem was discovered. Fix this by making use of walk_system_ram_range() to test the address range provided to __ioremap() against only RAM pages, rather than all lowmem pages. This means that if we have a lowmem I/O region, which is very common for MIPS systems, we're free to ioremap() address ranges within it. A nice bonus is that the test is no longer limited to lowmem. The approach here matches the way x86 performed the same test after commit c81c8a1eeede ("x86, ioremap: Speed up check for RAM pages") until x86 moved towards a slightly more complicated check using walk_mem_res() for unrelated reasons with commit 0e4c12b45aa8 ("x86/mm, resource: Use PAGE_KERNEL protection for ioremap of memory pages"). Signed-off-by: Paul Burton Reported-by: Serge Semin Tested-by: Serge Semin Fixes: 92923ca3aace ("mm: meminit: only set page reserved in the memblock region") Cc: James Hogan Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # v4.2+ Patchwork: https://patchwork.linux-mips.org/patch/19786/

Merge tag 'mips_4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

2018-06-12T19:56:02Z

Pull MIPS updates from James Hogan: "These are the main MIPS changes for 4.18. Rough overview: - MAINTAINERS: Add Paul Burton as MIPS co-maintainer - Misc: Generic compiler intrinsics, Y2038 improvements, Perf+MT fixes - Platform support: Netgear WNR1000 V3, Microsemi Ocelot integrated switch, Ingenic watchdog cleanups More detailed summary: Maintainers: - Add Paul Burton as MIPS co-maintainer, as I soon won't have access to much MIPS hardware, nor enough time to properly maintain MIPS on my own. Miscellaneous: - Use generic GCC library routines from lib/ - Add notrace to generic ucmpdi2 implementation - Rename compiler intrinsic selects to GENERIC_LIB_* - vmlinuz: Use generic ashldi3 - y2038: Convert update/read_persistent_clock() to *_clock64() - sni: Remove read_persistent_clock() - perf: Fix perf with MT counting other threads - Probe for per-TC perf counters in cpu-probe.c - Use correct VPE ID for VPE tracing Minor cleanups: - Avoid unneeded built-in.a in DTS dirs - sc-debugfs: Re-use kstrtobool_from_user - memset.S: Reinstate delay slot indentation - VPE: Fix spelling "uneeded" -> "Unneeded" Platform support: BCM47xx: - Add support for Netgear WNR1000 V3 - firmware: Support small NVRAM partitions - Use __initdata for LEDs platform data Ingenic: - Watchdog driver & platform code improvements: - Disable clock after stopping counter - Use devm_* functions - Drop module remove function - Move platform reset code to restart handler in driver - JZ4740: Convert watchdog instantiation to DT - JZ4780: Fix watchdog DT node - qi_lb60_defconfig: Enable watchdog driver Microsemi: - Ocelot: Add support for integrated switch - pcb123: Connect phys to ports" * tag 'mips_4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (30 commits) MAINTAINERS: Add Paul Burton as MIPS co-maintainer MIPS: ptrace: Make FPU context layout comments match reality MIPS: memset.S: Reinstate delay slot indentation MIPS: perf: Fix perf with MT counting other threads MIPS: perf: Use correct VPE ID when setting up VPE tracing MIPS: perf: More robustly probe for the presence of per-tc counters MIPS: Probe for MIPS MT perf counters per TC MIPS: mscc: Connect phys to ports on ocelot_pcb123 MIPS: mscc: Add switch to ocelot MIPS: JZ4740: Drop old platform reset code MIPS: qi_lb60: Enable the jz4740-wdt driver MIPS: JZ4780: dts: Fix watchdog node MIPS: JZ4740: dts: Add bindings for the jz4740-wdt driver watchdog: JZ4740: Drop module remove function watchdog: JZ4740: Register a restart handler watchdog: JZ4740: Use devm_* functions watchdog: JZ4740: Disable clock after stopping counter MIPS: VPE: Fix spelling mistake: "uneeded" -> "unneeded" MIPS: Re-use kstrtobool_from_user() MIPS: Convert update_persistent_clock() to update_persistent_clock64() ...

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

2018-06-04T22:23:48Z

Pull siginfo updates from Eric Biederman: "This set of changes close the known issues with setting si_code to an invalid value, and with not fully initializing struct siginfo. There remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64 and x86 to get the code that generates siginfo into a simpler and more maintainable state. Most of that work involves refactoring the signal handling code and thus careful code review. Also not included is the work to shrink the in kernel version of struct siginfo. That depends on getting the number of places that directly manipulate struct siginfo under control, as it requires the introduction of struct kernel_siginfo for the in kernel things. Overall this set of changes looks like it is making good progress, and with a little luck I will be wrapping up the siginfo work next development cycle" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) signal/sh: Stop gcc warning about an impossible case in do_divide_error signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions signal/um: More carefully relay signals in relay_signal. signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR} signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code signal/signalfd: Add support for SIGSYS signal/signalfd: Remove __put_user from signalfd_copyinfo signal/xtensa: Use force_sig_fault where appropriate signal/xtensa: Consistenly use SIGBUS in do_unaligned_user signal/um: Use force_sig_fault where appropriate signal/sparc: Use force_sig_fault where appropriate signal/sparc: Use send_sig_fault where appropriate signal/sh: Use force_sig_fault where appropriate signal/s390: Use force_sig_fault where appropriate signal/riscv: Replace do_trap_siginfo with force_sig_fault signal/riscv: Use force_sig_fault where appropriate signal/parisc: Use force_sig_fault where appropriate signal/parisc: Use force_sig_mceerr where appropriate signal/openrisc: Use force_sig_fault where appropriate signal/nios2: Use force_sig_fault where appropriate ...

Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping

2018-06-04T17:58:12Z

Pull dma-mapping updates from Christoph Hellwig: - replace the force_dma flag with a dma_configure bus method. (Nipun Gupta, although one patch is іncorrectly attributed to me due to a git rebase bug) - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai) - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the right thing for bounce buffering. - move dma-debug initialization to common code, and apply a few cleanups to the dma-debug code. - cleanup the Kconfig mess around swiotlb selection - swiotlb comment fixup (Yisheng Xie) - a trivial swiotlb fix. (Dan Carpenter) - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt) - add a new generic dma-noncoherent dma_map_ops implementation and use it for arc, c6x and nds32. - improve scatterlist validity checking in dma-debug. (Robin Murphy) - add a struct device quirk to limit the dma-mask to 32-bit due to bridge/system issues, and switch x86 to use it instead of a local hack for VIA bridges. - handle devices without a dma_mask more gracefully in the dma-direct code. * tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits) dma-direct: don't crash on device without dma_mask nds32: use generic dma_noncoherent_ops nds32: implement the unmap_sg DMA operation nds32: consolidate DMA cache maintainance routines x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag x86/pci-dma: remove the explicit nodac and allowdac option x86/pci-dma: remove the experimental forcesac boot option Documentation/x86: remove a stray reference to pci-nommu.c core, dma-direct: add a flag 32-bit dma limits dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs dma-debug: check scatterlist segments c6x: use generic dma_noncoherent_ops arc: use generic dma_noncoherent_ops arc: fix arc_dma_{map,unmap}_page arc: fix arc_dma_sync_sg_for_{cpu,device} arc: simplify arc_dma_sync_single_for_{cpu,device} dma-mapping: provide a generic dma-noncoherent implementation dma-mapping: simplify Kconfig dependencies riscv: add swiotlb support riscv: only enable ZONE_DMA32 for 64-bit ...

MIPS: Re-use kstrtobool_from_user()

2018-05-14T22:58:23Z

Re-use kstrtobool_from_user() instead of open coded variant. Signed-off-by: Andy Shevchenko Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Signed-off-by: James Hogan

MIPS: c-r4k: Fix data corruption related to cache coherence

2018-05-14T22:52:40Z

When DMA will be performed to a MIPS32 1004K CPS, the L1-cache for the range needs to be flushed and invalidated first. The code currently takes one of two approaches. 1/ If the range is less than the size of the dcache, then HIT type requests flush/invalidate cache lines for the particular addresses. HIT-type requests a globalised by the CPS so this is safe on SMP. 2/ If the range is larger than the size of dcache, then INDEX type requests flush/invalidate the whole cache. INDEX type requests affect the local cache only. CPS does not propagate them in any way. So this invalidation is not safe on SMP CPS systems. Data corruption due to '2' can quite easily be demonstrated by repeatedly "echo 3 > /proc/sys/vm/drop_caches" and then sha1sum a file that is several times the size of available memory. Dropping caches means that large contiguous extents (large than dcache) are more likely. This was not a problem before Linux-4.8 because option 2 was never used if CONFIG_MIPS_CPS was defined. The commit which removed that apparently didn't appreciate the full consequence of the change. We could, in theory, globalize the INDEX based flush by sending an IPI to other cores. These cache invalidation routines can be called with interrupts disabled and synchronous IPI require interrupts to be enabled. Asynchronous IPI may not trigger writeback soon enough. So we cannot use IPI in practice. We can already test if IPI would be needed for an INDEX operation with r4k_op_needs_ipi(R4K_INDEX). If this is true then we mustn't try the INDEX approach as we cannot use IPI. If this is false (e.g. when there is only one core and hence one L1 cache) then it is safe to use the INDEX approach without IPI. This patch avoids options 2 if r4k_op_needs_ipi(R4K_INDEX), and so eliminates the corruption. Fixes: c00ab4896ed5 ("MIPS: Remove cpu_has_safe_index_cacheops") Signed-off-by: NeilBrown Cc: Ralf Baechle Cc: Paul Burton Cc: linux-mips@linux-mips.org Cc: # 4.8+ Patchwork: https://patchwork.linux-mips.org/patch/19259/ Signed-off-by: James Hogan

dma-debug: move initialization to common code

2018-05-08T11:02:42Z

Most mainstream architectures are using 65536 entries, so lets stick to that. If someone is really desperate to override it that can still be done through , but I'd rather see a really good rationale for that. dma_debug_init is now called as a core_initcall, which for many architectures means much earlier, and provides dma-debug functionality earlier in the boot process. This should be safe as it only relies on the memory allocator already being available. Signed-off-by: Christoph Hellwig Acked-by: Marek Szyprowski Reviewed-by: Robin Murphy

signal/mips: Use force_sig_fault where appropriate

2018-04-25T15:41:02Z

Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared. Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info. In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer. Cc: Ralf Baechle Cc: James Hogan Cc: linux-mips@linux-mips.org Signed-off-by: "Eric W. Biederman"

signal: Ensure every siginfo we send has all bits initialized

2018-04-25T15:40:51Z

Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman"