kernel.git/arch/arm64/mm/ioremap.c, branch master

arm64: io: Rename ioremap_prot() to __ioremap_prot()

2026-02-25T19:49:51Z

Rename our ioremap_prot() implementation to __ioremap_prot() and convert all arch-internal callers over to the new function. ioremap_prot() remains as a #define to __ioremap_prot() for generic_access_phys() and will be subsequently extended to handle user permissions in 'prot'. Cc: Zeng Heng Cc: Jinjiang Tu Cc: Catalin Marinas Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon

arm64: mm: warn once for ioremap attempts on RAM mappings

2026-01-22T11:20:29Z

Replace WARN_ON with WARN_ONCE when detecting attempts to ioremap RAM. This prevents log spam when a misbehaving driver repeatedly tries to map RAM via ioremap. A single warning is more than enough to show the broken code path, and extra reports don't add extra information. Warning floods have been seen in production environments where broken external drivers hit this code path thousand of times, causing unnecessary messages to be printed and pressure on the serial console. Signed-off-by: Breno Leitao Acked-by: Catalin Marinas Signed-off-by: Will Deacon

mm/ioremap: pass pgprot_t to ioremap_prot() instead of unsigned long

2025-03-17T05:06:23Z

ioremap_prot() currently accepts pgprot_val parameter as an unsigned long, thus implicitly assuming that pgprot_val and pgprot_t could never be bigger than unsigned long. But this assumption soon will not be true on arm64 when using D128 pgtables. In 128 bit page table configuration, unsigned long is 64 bit, but pgprot_t is 128 bit. Passing platform abstracted pgprot_t argument is better as compared to size based data types. Let's change the parameter to directly pass pgprot_t like another similar helper generic_ioremap_prot(). Without this change in place, D128 configuration does not work on arm64 as the top 64 bits gets silently stripped when passing the protection value to this function. Link: https://lkml.kernel.org/r/20250218101954.415331-1-anshuman.khandual@arm.com Signed-off-by: Ryan Roberts Co-developed-by: Anshuman Khandual Signed-off-by: Anshuman Khandual Acked-by: Catalin Marinas [arm64] Signed-off-by: Andrew Morton

arm64: mm: Add confidential computing hook to ioremap_prot()

2024-08-30T15:30:41Z

Confidential Computing environments such as pKVM and Arm's CCA distinguish between shared (i.e. emulated) and private (i.e. assigned) MMIO regions. Introduce a hook into our implementation of ioremap_prot() so that MMIO regions can be shared if necessary. Reviewed-by: Catalin Marinas Reviewed-by: Steven Price Acked-by: Marc Zyngier Link: https://lore.kernel.org/r/20240830130150.8568-6-will@kernel.org Signed-off-by: Will Deacon

arm64 : mm: add wrapper function ioremap_prot()

2023-08-18T17:12:36Z

Since hook functions ioremap_allowed() and iounmap_allowed() will be obsoleted, add wrapper function ioremap_prot() to contain the the specific handling in addition to generic_ioremap_prot() invocation. Link: https://lkml.kernel.org/r/20230706154520.11257-19-bhe@redhat.com Signed-off-by: Baoquan He Reviewed-by: Christoph Hellwig Reviewed-by: Kefeng Wang Reviewed-by: Mike Rapoport (IBM) Acked-by: Catalin Marinas Cc: Catalin Marinas Cc: Will Deacon Cc: Alexander Gordeev Cc: Arnd Bergmann Cc: Brian Cain Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Chris Zankel Cc: David Laight Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Helge Deller Cc: "James E.J. Bottomley" Cc: John Paul Adrian Glaubitz Cc: Jonas Bonn Cc: Matthew Wilcox Cc: Max Filippov Cc: Michael Ellerman Cc: Nathan Chancellor Cc: Nicholas Piggin Cc: Niklas Schnelle Cc: Rich Felker Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Sven Schnelle Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Yoshinori Sato Signed-off-by: Andrew Morton

arm64: mm: Convert to GENERIC_IOREMAP

2022-06-27T11:22:31Z

Add hook for arm64's special operation when ioremap(), then ioremap_wc/np/cache is converted to use ioremap_prot() from GENERIC_IOREMAP, update the Copyright and kill the unused inclusions. Reviewed-by: Anshuman Khandual Acked-by: Catalin Marinas Signed-off-by: Kefeng Wang Link: https://lore.kernel.org/r/20220607125027.44946-6-wangkefeng.wang@huawei.com Signed-off-by: Will Deacon

arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear map

2022-05-10T00:34:28Z

The semantics of pfn_valid() is to check presence of the memory map for a PFN and not whether a PFN is covered by the linear map. The memory map may be present for NOMAP memory regions, but they won't be mapped in the linear mapping. Accessing such regions via __va() when they are memremap()'ed will cause a crash. On v5.4.y the crash happens on qemu-arm with UEFI [1]: <1>[ 0.084476] 8<--- cut here --- <1>[ 0.084595] Unable to handle kernel paging request at virtual address dfb76000 <1>[ 0.084938] pgd = (ptrval) <1>[ 0.085038] [dfb76000] *pgd=5f7fe801, *pte=00000000, *ppte=00000000 ... <4>[ 0.093923] [] (memcpy) from [] (dmi_setup+0x60/0x418) <4>[ 0.094204] [] (dmi_setup) from [] (arm_dmi_init+0x8/0x10) <4>[ 0.094408] [] (arm_dmi_init) from [] (do_one_initcall+0x50/0x228) <4>[ 0.094619] [] (do_one_initcall) from [] (kernel_init_freeable+0x15c/0x1f8) <4>[ 0.094841] [] (kernel_init_freeable) from [] (kernel_init+0x8/0x10c) <4>[ 0.095057] [] (kernel_init) from [] (ret_from_fork+0x14/0x2c) On kernels v5.10.y and newer the same crash won't reproduce on ARM because commit b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()") changed the way memory regions are registered in the resource tree, but that merely covers up the problem. On ARM64 memory resources registered in yet another way and there the issue of wrong usage of pfn_valid() to ensure availability of the linear map is also covered. Implement arch_memremap_can_ram_remap() on ARM and ARM64 to prevent access to NOMAP regions via the linear mapping in memremap(). Link: https://lore.kernel.org/all/Yl65zxGgFzF1Okac@sirena.org.uk Link: https://lkml.kernel.org/r/20220426060107.7618-1-rppt@kernel.org Signed-off-by: Mike Rapoport Reported-by: "kernelci.org bot" Tested-by: Mark Brown Reviewed-by: Ard Biesheuvel Acked-by: Catalin Marinas Cc: Greg Kroah-Hartman Cc: Mark Brown Cc: Mark-PK Tsai Cc: Russell King Cc: Tony Lindgren Cc: Will Deacon Cc: [5.4+] Signed-off-by: Andrew Morton

arm64: decouple check whether pfn is in linear map from pfn_valid()

2021-07-01T03:47:29Z

The intended semantics of pfn_valid() is to verify whether there is a struct page for the pfn in question and nothing else. Yet, on arm64 it is used to distinguish memory areas that are mapped in the linear map vs those that require ioremap() to access them. Introduce a dedicated pfn_is_map_memory() wrapper for memblock_is_map_memory() to perform such check and use it where appropriate. Using a wrapper allows to avoid cyclic include dependencies. While here also update style of pfn_valid() so that both pfn_valid() and pfn_is_map_memory() declarations will be consistent. Link: https://lkml.kernel.org/r/20210511100550.28178-4-rppt@kernel.org Signed-off-by: Mike Rapoport Acked-by: David Hildenbrand Acked-by: Ard Biesheuvel Reviewed-by: Kefeng Wang Cc: Anshuman Khandual Cc: Catalin Marinas Cc: Marc Zyngier Cc: Mark Rutland Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: remove unneeded includes of

2020-08-07T18:33:26Z

Patch series "mm: cleanup usage of " Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in and enable use of the generic functions where appropriate. In addition, functions declared and defined in headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the included all over the place. The first patch in this series removes unneeded includes of In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in and do not require that header. As for the other header files that used to include , it is possible to move that include into the .c file that actually uses symbols from and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [rppt@linux.ibm.com: fix powerpc warning] Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Reviewed-by: Pekka Enberg Acked-by: Geert Uytterhoeven [m68k] Cc: Abdul Haleem Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Christophe Leroy Cc: Joerg Roedel Cc: Max Filippov Cc: Peter Zijlstra Cc: Satheesh Rajendran Cc: Stafford Horne Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Joerg Roedel Cc: Matthew Wilcox Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org Signed-off-by: Linus Torvalds

arm64: remove __iounmap

2019-09-04T12:12:26Z

No need to indirect iounmap for arm64. Signed-off-by: Christoph Hellwig Signed-off-by: Will Deacon