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| author | Palmer Dabbelt <palmer@rivosinc.com> | 2024-07-31 09:22:00 -0700 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-09-20 01:32:39 -0700 |
| commit | ad380f6a0a5e82e794b45bb2eaec24ed51a56846 (patch) | |
| tree | 6224528f56c3f4f9b4b71b7be2bc401172daa71e /arch/riscv | |
| parent | 732b177663e1757950d73e7763fa0de26272439f (diff) | |
RISC-V: Don't have MAX_PHYSMEM_BITS exceed phys_addr_t
I recently ended up with a warning on some compilers along the lines of
CC kernel/resource.o
In file included from include/linux/ioport.h:16,
from kernel/resource.c:15:
kernel/resource.c: In function 'gfr_start':
include/linux/minmax.h:49:37: error: conversion from 'long long unsigned int' to 'resource_size_t' {aka 'unsigned int'} changes value from '17179869183' to '4294967295' [-Werror=overflow]
49 | ({ type ux = (x); type uy = (y); __cmp(op, ux, uy); })
| ^
include/linux/minmax.h:52:9: note: in expansion of macro '__cmp_once_unique'
52 | __cmp_once_unique(op, type, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~
include/linux/minmax.h:161:27: note: in expansion of macro '__cmp_once'
161 | #define min_t(type, x, y) __cmp_once(min, type, x, y)
| ^~~~~~~~~~
kernel/resource.c:1829:23: note: in expansion of macro 'min_t'
1829 | end = min_t(resource_size_t, base->end,
| ^~~~~
kernel/resource.c: In function 'gfr_continue':
include/linux/minmax.h:49:37: error: conversion from 'long long unsigned int' to 'resource_size_t' {aka 'unsigned int'} changes value from '17179869183' to '4294967295' [-Werror=overflow]
49 | ({ type ux = (x); type uy = (y); __cmp(op, ux, uy); })
| ^
include/linux/minmax.h:52:9: note: in expansion of macro '__cmp_once_unique'
52 | __cmp_once_unique(op, type, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_))
| ^~~~~~~~~~~~~~~~~
include/linux/minmax.h:161:27: note: in expansion of macro '__cmp_once'
161 | #define min_t(type, x, y) __cmp_once(min, type, x, y)
| ^~~~~~~~~~
kernel/resource.c:1847:24: note: in expansion of macro 'min_t'
1847 | addr <= min_t(resource_size_t, base->end,
| ^~~~~
cc1: all warnings being treated as errors
which looks like a real problem: our phys_addr_t is only 32 bits now, so
having 34-bit masks is just going to result in overflows.
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240731162159.9235-2-palmer@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/include/asm/sparsemem.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/riscv/include/asm/sparsemem.h b/arch/riscv/include/asm/sparsemem.h index 63acaecc3374..2f901a410586 100644 --- a/arch/riscv/include/asm/sparsemem.h +++ b/arch/riscv/include/asm/sparsemem.h @@ -7,7 +7,7 @@ #ifdef CONFIG_64BIT #define MAX_PHYSMEM_BITS 56 #else -#define MAX_PHYSMEM_BITS 34 +#define MAX_PHYSMEM_BITS 32 #endif /* CONFIG_64BIT */ #define SECTION_SIZE_BITS 27 #endif /* CONFIG_SPARSEMEM */ |