kernel/linux.git/arch/nios2/include/asm/pgtable.h, branch v6.12.80

nios2: define virtual address space for modules

2024-05-14T07:31:43+00:00

nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26 cannot reach all of vmalloc address space. Define module space as 32MiB below the kernel base and switch nios2 to use vmalloc for module allocations. Suggested-by: Thomas Gleixner Acked-by: Dinh Nguyen Acked-by: Song Liu Signed-off-by: Mike Rapoport (IBM) Signed-off-by: Luis Chamberlain

nios2/pgtable: define PFN_PTE_SHIFT

2024-02-22T18:24:50+00:00

We want to make use of pte_next_pfn() outside of set_ptes(). Let's simply define PFN_PTE_SHIFT, required by pte_next_pfn(). Link: https://lkml.kernel.org/r/20240129124649.189745-4-david@redhat.com Signed-off-by: David Hildenbrand Tested-by: Ryan Roberts Reviewed-by: Mike Rapoport (IBM) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Aneesh Kumar K.V Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christophe Leroy Cc: David S. Miller Cc: Dinh Nguyen Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Matthew Wilcox Cc: Michael Ellerman Cc: Naveen N. Rao Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Russell King (Oracle) Cc: Sven Schnelle Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton

Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-08-31T19:20:12+00:00

Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is providing protection against return oriented programming attacks. It works by maintaining a secondary (shadow) stack using a special memory type that has protections against modification. When executing a CALL instruction, the processor pushes the return address to both the normal stack and to the special permission shadow stack. Upon RET, the processor pops the shadow stack copy and compares it to the normal stack copy. For more information, refer to the links below for the earlier versions of this patch set" Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/ Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/ * tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits) x86/shstk: Change order of __user in type x86/ibt: Convert IBT selftest to asm x86/shstk: Don't retry vm_munmap() on -EINTR x86/kbuild: Fix Documentation/ reference x86/shstk: Move arch detail comment out of core mm x86/shstk: Add ARCH_SHSTK_STATUS x86/shstk: Add ARCH_SHSTK_UNLOCK x86: Add PTRACE interface for shadow stack selftests/x86: Add shadow stack test x86/cpufeatures: Enable CET CR4 bit for shadow stack x86/shstk: Wire in shadow stack interface x86: Expose thread features in /proc/$PID/status x86/shstk: Support WRSS for userspace x86/shstk: Introduce map_shadow_stack syscall x86/shstk: Check that signal frame is shadow stack mem x86/shstk: Check that SSP is aligned on sigreturn x86/shstk: Handle signals for shadow stack x86/shstk: Introduce routines modifying shstk x86/shstk: Handle thread shadow stack x86/shstk: Add user-mode shadow stack support ...

nios2: implement the new page table range API

2023-08-24T23:20:22+00:00

Add set_ptes(), update_mmu_cache_range(), flush_icache_pages() and flush_dcache_folio(). Change the PG_arch_1 (aka PG_dcache_dirty) flag from being per-page to per-folio. Link: https://lkml.kernel.org/r/20230802151406.3735276-19-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Mike Rapoport (IBM) Cc: Dinh Nguyen Signed-off-by: Andrew Morton

mm: Rename arch pte_mkwrite()'s to pte_mkwrite_novma()

2023-07-11T21:10:56+00:00

The x86 Shadow stack feature includes a new type of memory called shadow stack. This shadow stack memory has some unusual properties, which requires some core mm changes to function properly. One of these unusual properties is that shadow stack memory is writable, but only in limited ways. These limits are applied via a specific PTE bit combination. Nevertheless, the memory is writable, and core mm code will need to apply the writable permissions in the typical paths that call pte_mkwrite(). The goal is to make pte_mkwrite() take a VMA, so that the x86 implementation of it can know whether to create regular writable or shadow stack mappings. But there are a couple of challenges to this. Modifying the signatures of each arch pte_mkwrite() implementation would be error prone because some are generated with macros and would need to be re-implemented. Also, some pte_mkwrite() callers operate on kernel memory without a VMA. So this can be done in a three step process. First pte_mkwrite() can be renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite() added that just calls pte_mkwrite_novma(). Next callers without a VMA can be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers can be changed to take/pass a VMA. Start the process by renaming pte_mkwrite() to pte_mkwrite_novma() and adding the pte_mkwrite() wrapper in linux/pgtable.h. Apply the same pattern for pmd_mkwrite(). Since not all archs have a pmd_mkwrite_novma(), create a new arch config HAS_HUGE_PAGE that can be used to tell if pmd_mkwrite() should be defined. Otherwise in the !HAS_HUGE_PAGE cases the compiler would not be able to find pmd_mkwrite_novma(). No functional change. Suggested-by: Linus Torvalds Signed-off-by: Rick Edgecombe Signed-off-by: Dave Hansen Reviewed-by: Mike Rapoport (IBM) Acked-by: Geert Uytterhoeven Acked-by: David Hildenbrand Link: https://lore.kernel.org/lkml/CAHk-=wiZjSu7c9sFYZb3q04108stgHff2wfbokGCCgW7riz+8Q@mail.gmail.com/ Link: https://lore.kernel.org/all/20230613001108.3040476-2-rick.p.edgecombe%40intel.com

mm: remove __HAVE_ARCH_PTE_SWP_EXCLUSIVE

2023-02-03T06:33:11+00:00

__HAVE_ARCH_PTE_SWP_EXCLUSIVE is now supported by all architectures that support swp PTEs, so let's drop it. Link: https://lkml.kernel.org/r/20230113171026.582290-27-david@redhat.com Signed-off-by: David Hildenbrand Signed-off-by: Andrew Morton

nios2/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE

2023-02-03T06:33:08+00:00

Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by using the yet-unused bit 31. Link: https://lkml.kernel.org/r/20230113171026.582290-15-david@redhat.com Signed-off-by: David Hildenbrand Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton

nios2/mm: refactor swap PTE layout

2023-02-03T06:33:08+00:00

nios2 disables swap for a good reason: it doesn't even provide sufficient type bits as required by core MM. However, swap entries are nowadays also used for other purposes (migration entries, PTE markers, HWPoison, ...), and accidential use could be problematic. Let's properly use 5 bits for the swap type and document the layout. Bits 26--31 should get ignored by hardware completely, so they can be used. Link: https://lkml.kernel.org/r/20230113171026.582290-14-david@redhat.com Signed-off-by: David Hildenbrand Cc: Dinh Nguyen Signed-off-by: Andrew Morton

mm: remove kern_addr_valid() completely

2022-11-09T01:37:18+00:00

Most architectures (except arm64/x86/sparc) simply return 1 for kern_addr_valid(), which is only used in read_kcore(), and it calls copy_from_kernel_nofault() which could check whether the address is a valid kernel address. So as there is no need for kern_addr_valid(), let's remove it. Link: https://lkml.kernel.org/r/20221018074014.185687-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Geert Uytterhoeven [m68k] Acked-by: Heiko Carstens [s390] Acked-by: Christoph Hellwig Acked-by: Helge Deller [parisc] Acked-by: Michael Ellerman [powerpc] Acked-by: Guo Ren [csky] Acked-by: Catalin Marinas [arm64] Cc: Alexander Gordeev Cc: Andy Lutomirski Cc: Anton Ivanov Cc: Cc: Borislav Petkov Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Chris Zankel Cc: Dave Hansen Cc: David S. Miller Cc: Dinh Nguyen Cc: Greg Ungerer Cc: H. Peter Anvin Cc: Huacai Chen Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: James Bottomley Cc: Johannes Berg Cc: Jonas Bonn Cc: Matt Turner Cc: Max Filippov Cc: Michal Simek Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Richard Henderson Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Sven Schnelle Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Cc: Xuerui Wang Cc: Yoshinori Sato Signed-off-by: Andrew Morton

nios2: drop definition of PGD_ORDER

2022-07-18T00:14:43+00:00

This is the order of the page table allocation, not the order of a PGD. Since its always hardwired to 0, simply drop it. Link: https://lkml.kernel.org/r/20220703141203.147893-9-rppt@kernel.org Signed-off-by: Mike Rapoport Acked-by: Dinh Nguyen Cc: Arnd Bergmann Cc: Guo Ren Cc: Helge Deller Cc: Huacai Chen Cc: James Bottomley Cc: "Matthew Wilcox (Oracle)" Cc: Max Filippov Cc: Thomas Bogendoerfer Cc: Xuerui Wang Signed-off-by: Andrew Morton