kernel.git/arch/arm64/mm, branch linux-4.10.y

arm64: mm: unaligned access by user-land should be received as SIGBUS

2017-04-12T10:42:04Z

commit 09a6adf53d42ca3088fa3fb41f40b768efc711ed upstream. After 52d7523 (arm64: mm: allow the kernel to handle alignment faults on user accesses) commit user-land accesses that produce unaligned exceptions like in case of aarch32 ldm/stm/ldrd/strd instructions operating on unaligned memory received by user-land as SIGSEGV. It is wrong, it should be reported as SIGBUS as it was before 52d7523 commit. Changed do_bad_area function to take signal and code parameters out of esr value using fault_info table, so in case of do_alignment_fault fault user-land will receive SIGBUS. Wrapped access to fault_info table into esr_to_fault_info function. Fixes: 52d7523 (arm64: mm: allow the kernel to handle alignment faults on user accesses) Signed-off-by: Victor Kamensky Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

Revert "arm64: mm: set the contiguous bit for kernel mappings where appropriate"

2017-03-12T05:44:15Z

commit d81bbe6d882461dec4b71dbe2aa85565fcca4187 upstream. This reverts commit 0bfc445dec9dd8130d22c9f4476eed7598524129. When we change the permissions of regions mapped using contiguous entries, the architecture requires us to follow a Break-Before-Make strategy, breaking *all* associated entries before we can change any of the following properties from the entries: - presence of the contiguous bit - output address - attributes - permissiones Failure to do so can result in a number of problems (e.g. TLB conflict aborts and/or erroneous results from TLB lookups). See ARM DDI 0487A.k_iss10775, "Misprogramming of the Contiguous bit", page D4-1762. We do not take this into account when altering the permissions of kernel segments in mark_rodata_ro(), where we change the permissions of live contiguous entires one-by-one, leaving them transiently inconsistent. This has been observed to result in failures on some fast model configurations. Unfortunately, we cannot follow Break-Before-Make here as we'd have to unmap kernel text and data used to perform the sequence. For the timebeing, revert commit 0bfc445dec9dd813 so as to avoid issues resulting from this misuse of the contiguous bit. Signed-off-by: Mark Rutland Acked-by: Ard Biesheuvel Reported-by: Jean-Philippe Brucker Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: dma-mapping: Fix dma_mapping_error() when bypassing SWIOTLB

2017-03-12T05:44:15Z

commit adbe7e26f4257f72817495b9bce114284060b0d7 upstream. When bypassing SWIOTLB on small-memory systems, we need to avoid calling into swiotlb_dma_mapping_error() in exactly the same way as we avoid swiotlb_dma_supported(), because the former also relies on SWIOTLB state being initialised. Under the assumptions for which we skip SWIOTLB, dma_map_{single,page}() will only ever return the DMA-offset-adjusted physical address of the page passed in, thus we can report success unconditionally. Fixes: b67a8b29df7e ("arm64: mm: only initialize swiotlb when necessary") CC: Jisheng Zhang Reported-by: Aaro Koskinen Signed-off-by: Robin Murphy Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: Fix swiotlb fallback allocation

2017-01-17T11:48:11Z

Commit b67a8b29df introduced logic to skip swiotlb allocation when all memory is DMA accessible anyway. While this is a great idea, __dma_alloc still calls swiotlb code unconditionally to allocate memory when there is no CMA memory available. The swiotlb code is called to ensure that we at least try get_free_pages(). Without initialization, swiotlb allocation code tries to access io_tlb_list which is NULL. That results in a stack trace like this: Unable to handle kernel NULL pointer dereference at virtual address 00000000 [...] [] swiotlb_tbl_map_single+0xd0/0x2b0 [] swiotlb_alloc_coherent+0x10c/0x198 [] __dma_alloc+0x68/0x1a8 [] drm_gem_cma_create+0x98/0x108 [drm] [] drm_fbdev_cma_create_with_funcs+0xbc/0x368 [drm_kms_helper] [] drm_fbdev_cma_create+0x2c/0x40 [drm_kms_helper] [] drm_fb_helper_initial_config+0x238/0x410 [drm_kms_helper] [] drm_fbdev_cma_init_with_funcs+0x98/0x160 [drm_kms_helper] [] drm_fbdev_cma_init+0x40/0x58 [drm_kms_helper] [] vc4_kms_load+0x90/0xf0 [vc4] [] vc4_drm_bind+0xec/0x168 [vc4] [...] Thankfully swiotlb code just learned how to not do allocations with the FORCE_NO option. This patch configures the swiotlb code to use that if we decide not to initialize the swiotlb framework. Fixes: b67a8b29df ("arm64: mm: only initialize swiotlb when necessary") Signed-off-by: Alexander Graf CC: Jisheng Zhang CC: Geert Uytterhoeven CC: Konrad Rzeszutek Wilk Signed-off-by: Catalin Marinas

arm64: hugetlb: fix the wrong return value for huge_ptep_set_access_flags

2017-01-11T10:26:40Z

In current code, the @changed always returns the last one's status for the huge page with the contiguous bit set. This is really not what we want. Even one of the PTEs is changed, we should tell it to the caller. This patch fixes this issue. Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit") Cc: # 4.5.x- Signed-off-by: Huang Shijie Signed-off-by: Catalin Marinas

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2017-01-06T23:18:58Z

Pull arm64 fixes from Catalin Marinas: - re-introduce the arm64 get_current() optimisation - KERN_CONT fallout fix in show_pte() * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: restore get_current() optimisation arm64: mm: fix show_pte KERN_CONT fallout

Merge branch 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb

2017-01-06T18:53:21Z

Pull swiotlb fixes from Konrad Rzeszutek Wilk: "This has one fix to make i915 work when using Xen SWIOTLB, and a feature from Geert to aid in debugging of devices that can't do DMA outside the 32-bit address space. The feature from Geert is on top of v4.10 merge window commit (specifically you pulling my previous branch), as his changes were dependent on the Documentation/ movement patches. I figured it would just easier than me trying than to cherry-pick the Documentation patches to satisfy git. The patches have been soaking since 12/20, albeit I updated the last patch due to linux-next catching an compiler error and adding an Tested-and-Reported-by tag" * 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb: Export swiotlb_max_segment to users swiotlb: Add swiotlb=noforce debug option swiotlb: Convert swiotlb_force from int to enum x86, swiotlb: Simplify pci_swiotlb_detect_override()

arm64: mm: fix show_pte KERN_CONT fallout

2017-01-04T16:25:50Z

Recent changes made KERN_CONT mandatory for continued lines. In the absence of KERN_CONT, a newline may be implicit inserted by the core printk code. In show_pte, we (erroneously) use printk without KERN_CONT for continued prints, resulting in output being split across a number of lines, and not matching the intended output, e.g. [ff000000000000] *pgd=00000009f511b003 , *pud=00000009f4a80003 , *pmd=0000000000000000 Fix this by using pr_cont() for all the continuations. Acked-by: Will Deacon Signed-off-by: Mark Rutland Signed-off-by: Catalin Marinas

arm64: don't pull uaccess.h into *.S

2016-12-26T18:05:17Z

Split asm-only parts of arm64 uaccess.h into a new header and use that from *.S. Signed-off-by: Al Viro

Replace with globally

2016-12-24T19:46:01Z

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds