kernel/linux.git/arch/nios2/include, branch v5.10.251

nios2: force update_mmu_cache on spurious tlb-permission--related pagefaults

2025-06-27T10:04:17+00:00

[ Upstream commit 2d8a3179ea035f9341b6a73e5ba4029fc67e983d ] NIOS2 uses a software-managed TLB for virtual address translation. To flush a cache line, the original mapping is replaced by one to physical address 0x0 with no permissions (rwx mapped to 0) set. This can lead to TLB-permission--related traps when such a nominally flushed entry is encountered as a mapping for an otherwise valid virtual address within a process (e.g. due to an MMU-PID-namespace rollover that previously flushed the complete TLB including entries of existing, running processes). The default ptep_set_access_flags implementation from mm/pgtable-generic.c only forces a TLB-update when the page-table entry has changed within the page table: /* * [...] We return whether the PTE actually changed, which in turn * instructs the caller to do things like update__mmu_cache. [...] */ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, pte_t *ptep, pte_t entry, int dirty) { int changed = !pte_same(*ptep, entry); if (changed) { set_pte_at(vma->vm_mm, address, ptep, entry); flush_tlb_fix_spurious_fault(vma, address); } return changed; } However, no cross-referencing with the TLB-state occurs, so the flushing-induced pseudo entries that are responsible for the pagefault in the first place are never pre-empted from TLB on this code path. This commit fixes this behaviour by always requesting a TLB-update in this part of the pagefault handling, fixing spurious page-faults on the way. The handling is a straightforward port of the logic from the MIPS architecture via an arch-specific ptep_set_access_flags function ported from arch/mips/include/asm/pgtable.h. Signed-off-by: Simon Schuster Signed-off-by: Andreas Oetken Signed-off-by: Dinh Nguyen Signed-off-by: Sasha Levin

nios32: add support for TIF_NOTIFY_SIGNAL

2023-01-04T10:39:19+00:00

[ Upstream commit 42020064274c235d720d9c4b7d9a678b133e59cf ] Wire up TIF_NOTIFY_SIGNAL handling for nios32. Cc: Ley Foon Tan Acked-by: Ley Foon Tan Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

nios2: add force_successful_syscall_return()

2022-08-25T09:38:04+00:00

commit fd0c153daad135d0ec1a53c5dbe6936a724d6ae1 upstream. If we use the ancient SysV syscall ABI, we'd better have tell the kernel how to claim that a negative return value is a success. Use ->orig_r2 for that - it's inaccessible via ptrace, so it's a fair game for changes and it's normally[*] non-negative on return from syscall. Set to -1; syscall is not going to be restart-worthy by definition, so we won't interfere with that use either. [*] the only exception is rt_sigreturn(), where we skip the entire messing with r1/r2 anyway. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro Signed-off-by: Dinh Nguyen Signed-off-by: Greg Kroah-Hartman

nios2: page fault et.al. are not restartable syscalls...

2022-08-25T09:38:03+00:00

commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream. make sure that ->orig_r2 is negative for everything except the syscalls. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro Signed-off-by: Dinh Nguyen Signed-off-by: Greg Kroah-Hartman

nios2: use fallback for random_get_entropy() instead of zero

2022-05-30T07:33:41+00:00

commit c04e72700f2293013dab40208e809369378f224c upstream. In the event that random_get_entropy() can't access a cycle counter or similar, falling back to returning 0 is really not the best we can do. Instead, at least calling random_get_entropy_fallback() would be preferable, because that always needs to return _something_, even falling back to jiffies eventually. It's not as though random_get_entropy_fallback() is super high precision or guaranteed to be entropic, but basically anything that's not zero all the time is better than returning zero all the time. Cc: Thomas Gleixner Cc: Arnd Bergmann Acked-by: Dinh Nguyen Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

uaccess: fix nios2 and microblaze get_user_8()

2022-04-08T12:40:08+00:00

[ Upstream commit a97b693c3712f040c5802f32b2d685352e08cefa ] These two architectures implement 8-byte get_user() through a memcpy() into a four-byte variable, which won't fit. Use a temporary 64-bit variable instead here, and use a double cast the way that risc-v and openrisc do to avoid compile-time warnings. Fixes: 6a090e97972d ("arch/microblaze: support get_user() of size 8 bytes") Fixes: 5ccc6af5e88e ("nios2: Memory management") Reviewed-by: Christoph Hellwig Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann Signed-off-by: Sasha Levin

NIOS2: irqflags: rename a redefined register name

2021-10-27T07:56:48+00:00

[ Upstream commit 4cce60f15c04d69eff6ffc539ab09137dbe15070 ] Both arch/nios2/ and drivers/mmc/host/tmio_mmc.c define a macro with the name "CTL_STATUS". Change the one in arch/nios2/ to be "CTL_FSTATUS" (flags status) to eliminate the build warning. In file included from ../drivers/mmc/host/tmio_mmc.c:22: drivers/mmc/host/tmio_mmc.h:31: warning: "CTL_STATUS" redefined 31 | #define CTL_STATUS 0x1c arch/nios2/include/asm/registers.h:14: note: this is the location of the previous definition 14 | #define CTL_STATUS 0 Fixes: b31ebd8055ea ("nios2: Nios2 registers") Signed-off-by: Randy Dunlap Cc: Dinh Nguyen Signed-off-by: Dinh Nguyen Signed-off-by: Sasha Levin

unify generic instances of csum_partial_copy_nocheck()

2020-08-20T19:45:14+00:00

quite a few architectures have the same csum_partial_copy_nocheck() - simply memcpy() the data and then return the csum of the copy. hexagon, parisc, ia64, s390, um: explicitly spelled out that way. arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32, nios2, openrisc, riscv, unicore32: end up picking the same thing spelled out in lib/checksum.h (with varying amounts of perversions along the way). everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc, sh, sparc, x86, xtensa) have non-generic variants. For all except c6x the declaration is in their asm/checksum.h. c6x uses the wrapper from asm-generic/checksum.h that would normally lead to the lib/checksum.h instance, but in case of c6x we end up using an asm function from arch/c6x instead. Screw that mess - have architectures with private instances define _HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY *not* defined. Signed-off-by: Al Viro

uaccess: remove segment_eq

2020-08-12T17:57:58+00:00

segment_eq is only used to implement uaccess_kernel. Just open code uaccess_kernel in the arch uaccess headers and remove one layer of indirection. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Acked-by: Linus Torvalds Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven Cc: Nick Hu Cc: Vincent Chen Cc: Paul Walmsley Cc: Palmer Dabbelt Link: http://lkml.kernel.org/r/20200710135706.537715-5-hch@lst.de Signed-off-by: Linus Torvalds

asm-generic: pgalloc: provide generic pgd_free()

2020-08-07T18:33:26+00:00

Most architectures define pgd_free() as a wrapper for free_page(). Provide a generic version in asm-generic/pgalloc.h and enable its use for most architectures. 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: Joerg Roedel Cc: Max Filippov Cc: Peter Zijlstra (Intel) Cc: Satheesh Rajendran Cc: Stafford Horne Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Matthew Wilcox Link: http://lkml.kernel.org/r/20200627143453.31835-7-rppt@kernel.org Signed-off-by: Linus Torvalds