kernel.git/arch/riscv/include, branch linux-6.0.y

riscv: uaccess: fix type of 0 variable on error in get_user()

2023-01-12T11:00:47Z

commit b9b916aee6715cd7f3318af6dc360c4729417b94 upstream. If the get_user(x, ptr) has x as a pointer, then the setting of (x) = 0 is going to produce the following sparse warning, so fix this by forcing the type of 'x' when access_ok() fails. fs/aio.c:2073:21: warning: Using plain integer as NULL pointer Signed-off-by: Ben Dooks Reviewed-by: Palmer Dabbelt Link: https://lore.kernel.org/r/20221229170545.718264-1-ben-linux@fluff.org Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: mm: notify remote harts about mmu cache updates

2023-01-07T10:15:57Z

commit 4bd1d80efb5af640f99157f39b50fb11326ce641 upstream. Current implementation of update_mmu_cache function performs local TLB flush. It does not take into account ASID information. Besides, it does not take into account other harts currently running the same mm context or possible migration of the running context to other harts. Meanwhile TLB flush is not performed for every context switch if ASID support is enabled. Patch [1] proposed to add ASID support to update_mmu_cache to avoid flushing local TLB entirely. This patch takes into account other harts currently running the same mm context as well as possible migration of this context to other harts. For this purpose the approach from flush_icache_mm is reused. Remote harts currently running the same mm context are informed via SBI calls that they need to flush their local TLBs. All the other harts are marked as needing a deferred TLB flush when this mm context runs on them. [1] https://lore.kernel.org/linux-riscv/20220821013926.8968-1-tjytimi@163.com/ Signed-off-by: Sergey Matyukevich Fixes: 65d4b9c53017 ("RISC-V: Implement ASID allocator") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/linux-riscv/20220829205219.283543-1-geomatsi@gmail.com/#t Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

RISC-V: kexec: Fix memory leak of fdt buffer

2023-01-07T10:15:56Z

commit 96df59b1ae23f5c11698c3c2159aeb2ecd4944a4 upstream. This is reported by kmemleak detector: unreferenced object 0xff60000082864000 (size 9588): comm "kexec", pid 146, jiffies 4294900634 (age 64.788s) hex dump (first 32 bytes): d0 0d fe ed 00 00 12 ed 00 00 00 48 00 00 11 40 ...........H...@ 00 00 00 28 00 00 00 11 00 00 00 02 00 00 00 00 ...(............ backtrace: [<00000000f95b17c4>] kmemleak_alloc+0x34/0x3e [<00000000b9ec8e3e>] kmalloc_order+0x9c/0xc4 [<00000000a95cf02e>] kmalloc_order_trace+0x34/0xb6 [<00000000f01e68b4>] __kmalloc+0x5c2/0x62a [<000000002bd497b2>] kvmalloc_node+0x66/0xd6 [<00000000906542fa>] of_kexec_alloc_and_setup_fdt+0xa6/0x6ea [<00000000e1166bde>] elf_kexec_load+0x206/0x4ec [<0000000036548e09>] kexec_image_load_default+0x40/0x4c [<0000000079fbe1b4>] sys_kexec_file_load+0x1c4/0x322 [<0000000040c62c03>] ret_from_syscall+0x0/0x2 In elf_kexec_load(), a buffer is allocated via kvmalloc() to store fdt. While it's not freed back to system when kexec kernel is reloaded or unloaded. Then memory leak is caused. Fix it by introducing riscv specific function arch_kimage_file_post_load_cleanup(), and freeing the buffer there. Fixes: 6261586e0c91 ("RISC-V: Add kexec_file support") Signed-off-by: Li Huafei Reviewed-by: Conor Dooley Reviewed-by: Liao Chang Link: https://lore.kernel.org/r/20221104095658.141222-1-lihuafei1@huawei.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: Fix P4D_SHIFT definition for 3-level page table mode

2022-12-31T12:26:23Z

[ Upstream commit 71fc3621efc38ace9640ee6a0db3300900689592 ] RISC-V kernels support 3,4,5-level page tables at runtime by folding upper levels. In case of a 3-level page table, PGDIR is folded into P4D which in turn is folded into PUD: PGDIR_SHIFT value is correctly set to the same value as PUD_SHIFT, but P4D_SHIFT is not, then any use of P4D_SHIFT will access invalid address bits (all set to 1). Fix this by dynamically defining P4D_SHIFT value, like we already do for PGDIR_SHIFT. Fixes: d10efa21a937 ("riscv: mm: Control p4d's folding by pgtable_l5_enabled") Signed-off-by: Alexandre Ghiti Reviewed-by: Palmer Dabbelt Link: https://lore.kernel.org/r/20221201135128.1482189-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

RISC-V: Fix MEMREMAP_WB for systems with Svpbmt

2022-12-31T12:26:23Z

[ Upstream commit b91676fc16cd384a81e3af52c641aa61985cc231 ] Currently, the memremap() called with MEMREMAP_WB maps memory using the generic ioremap() function which breaks on system with Svpbmt because memory mapped using _PAGE_IOREMAP page attributes is treated as strongly-ordered non-cacheable IO memory. To address this, we implement RISC-V specific arch_memremap_wb() which maps memory using _PAGE_KERNEL page attributes resulting in write-back cacheable mapping on systems with Svpbmt. Fixes: ff689fd21cb1 ("riscv: add RISC-V Svpbmt extension support") Co-developed-by: Mayuresh Chitale Signed-off-by: Mayuresh Chitale Signed-off-by: Anup Patel Acked-by: Conor Dooley Link: https://lore.kernel.org/r/20221114090536.1662624-2-apatel@ventanamicro.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv/mm: add arch hook arch_clear_hugepage_flags

2022-12-31T12:26:22Z

[ Upstream commit d8bf77a1dc3079692f54be3087a5fd16d90027b0 ] With the PG_arch_1 we keep track if the page's data cache is clean, architecture rely on this property to treat new pages as dirty with respect to the data cache and perform the flushing before mapping the pages into userspace. This patch adds a new architecture hook, arch_clear_hugepage_flags,so that architectures which rely on the page flags being in a particular state for fresh allocations can adjust the flags accordingly when a page is freed into the pool. Fixes: 9e953cda5cdf ("riscv: Introduce huge page support for 32/64bit kernel") Signed-off-by: Tong Tiangen Link: https://lore.kernel.org/r/20221024094725.3054311-3-tongtiangen@huawei.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: fix race when vmap stack overflow

2022-12-08T10:30:20Z

[ Upstream commit 7e1864332fbc1b993659eab7974da9fe8bf8c128 ] Currently, when detecting vmap stack overflow, riscv firstly switches to the so called shadow stack, then use this shadow stack to call the get_overflow_stack() to get the overflow stack. However, there's a race here if two or more harts use the same shadow stack at the same time. To solve this race, we introduce spin_shadow_stack atomic var, which will be swap between its own address and 0 in atomic way, when the var is set, it means the shadow_stack is being used; when the var is cleared, it means the shadow_stack isn't being used. Fixes: 31da94c25aea ("riscv: add VMAP_STACK overflow detection") Signed-off-by: Jisheng Zhang Suggested-by: Guo Ren Reviewed-by: Guo Ren Link: https://lore.kernel.org/r/20221030124517.2370-1-jszhang@kernel.org [Palmer: Add AQ to the swap, and also some comments.] Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: Sync efi page table's kernel mappings before switching

2022-12-08T10:30:20Z

[ Upstream commit 3f105a742725a1b78766a55169f1d827732e62b8 ] The EFI page table is initially created as a copy of the kernel page table. With VMAP_STACK enabled, kernel stacks are allocated in the vmalloc area: if the stack is allocated in a new PGD (one that was not present at the moment of the efi page table creation or not synced in a previous vmalloc fault), the kernel will take a trap when switching to the efi page table when the vmalloc kernel stack is accessed, resulting in a kernel panic. Fix that by updating the efi kernel mappings before switching to the efi page table. Signed-off-by: Alexandre Ghiti Fixes: b91540d52a08 ("RISC-V: Add EFI runtime services") Tested-by: Emil Renner Berthing Reviewed-by: Atish Patra Link: https://lore.kernel.org/r/20221121133303.1782246-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: fix detection of toolchain Zihintpause support

2022-11-03T15:00:35Z

[ Upstream commit aae538cd03bc8fc35979653d9180922d146da0ca ] It is not sufficient to check if a toolchain supports a particular extension without checking if the linker supports that extension too. For example, Clang 15 supports Zihintpause but GNU bintutils 2.35.2 does not, leading build errors like so: riscv64-linux-gnu-ld: -march=rv64i2p0_m2p0_a2p0_c2p0_zihintpause2p0: Invalid or unknown z ISA extension: 'zihintpause' Add a TOOLCHAIN_HAS_ZIHINTPAUSE which checks if each of the compiler, assembler and linker support the extension. Replace the ifdef in the vdso with one depending on this new symbol. Fixes: 8eb060e10185 ("arch/riscv: add Zihintpause support") Signed-off-by: Conor Dooley Reviewed-by: Heiko Stuebner Reviewed-by: Nathan Chancellor Link: https://lore.kernel.org/r/20221006173520.1785507-3-conor@kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: jump_label: mark arguments as const to satisfy asm constraints

2022-11-03T15:00:32Z

[ Upstream commit 89fd4a1df829187d4d35f6a520cc531de622e6f0 ] Samuel reported that the static branch usage in cpu_relax() breaks building with CONFIG_CC_OPTIMIZE_FOR_SIZE: In file included from : ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 probably does not match constraints 285 | #define asm_volatile_goto(x...) asm goto(x) | ^~~ ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro 'asm_volatile_goto' 41 | asm_volatile_goto( | ^~~~~~~~~~~~~~~~~ ././include/linux/compiler_types.h:285:33: error: impossible constraint in 'asm' 285 | #define asm_volatile_goto(x...) asm goto(x) | ^~~ ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro 'asm_volatile_goto' 41 | asm_volatile_goto( | ^~~~~~~~~~~~~~~~~ make[1]: *** [scripts/Makefile.build:249: arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 Maybe "-Os" prevents GCC from detecting that the key/branch arguments can be treated as constants and used as immediate operands. Inspired by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to satisfy asm constraints"), and as pointed out by Steven: "The "i" constraint needs to be a constant.", let's do similar modifications to riscv. Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. Link: https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ Link: https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ Fixes: 8eb060e10185 ("arch/riscv: add Zihintpause support") Reported-by: Samuel Holland Signed-off-by: Jisheng Zhang Reviewed-by: Andrew Jones Tested-by: Heiko Stuebner Link: https://lore.kernel.org/r/20221008145437.491-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin