RISC-V: Fix FIXMAP_TOP to avoid overlap with VMALLOC area

2019-03-29T06:16:04Z

The FIXMAP area overlaps with VMALLOC area in Linux-5.1-rc1 hence we get below warning in Linux RISC-V 32bit kernel. This warning does not show-up in Linux RISC-V 64bit kernel due to large VMALLOC area. WARNING: CPU: 0 PID: 22 at mm/vmalloc.c:150 vmap_page_range_noflush+0x134/0x15c Modules linked in: CPU: 0 PID: 22 Comm: kworker/0:1 Not tainted 5.1.0-rc1-00005-gebc2f658040e #1 Workqueue: events pcpu_balance_workfn Call Trace: [] walk_stackframe+0x0/0xa0 [] show_stack+0x28/0x32 [] dump_stack+0x62/0x7e [] __warn+0x98/0xce [] warn_slowpath_null+0x2e/0x3c [] vmap_page_range_noflush+0x134/0x15c [] map_kernel_range_noflush+0xc/0x14 [] pcpu_populate_chunk+0x19e/0x236 [] pcpu_balance_workfn+0x448/0x464 [] process_one_work+0x16c/0x2ea [] worker_thread+0xf2/0x3b2 [] kthread+0xce/0xdc [] ret_from_exception+0x0/0xc This patch fixes above warning by placing FIXMAP area below VMALLOC area. Fixes: f2c17aabc917 ("RISC-V: Implement compile-time fixed mappings") Signed-off-by: Anup Patel Reviewed-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt

RISC-V: Implement compile-time fixed mappings

2019-02-21T05:56:42Z

This patch implements compile-time virtual to physical mappings. These compile-time fixed mappings can be used by earlycon, ACPI, and early ioremap for creating fixed mappings when FIX_EARLYCON_MEM=y. To start with, we have enabled compile-time fixed mappings for earlycon. Signed-off-by: Anup Patel Reviewed-by: Christoph Hellwig Reviewed-by: Palmer Dabbelt

kernel/arch/riscv/include/asm/fixmap.h, branch linux-5.1.y

RISC-V: Fix FIXMAP_TOP to avoid overlap with VMALLOC area

RISC-V: Implement compile-time fixed mappings