Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'riscv-for-linus-6.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
- Another fix to avoid allocating pages that overlap with ERR_PTR,
which manifests on rv32
- A revert for the badaccess patch I incorrectly picked up an early
version of
* tag 'riscv-for-linus-6.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
Revert "riscv: mm: accelerate pagefault when badaccess"
riscv: fix overlap of allocated page and PTR_ERR
+13
-12
+2
-2
arch/riscv/mm/fault.c
+2
-2
arch/riscv/mm/fault.c
···
293
293
if (unlikely(access_error(cause, vma))) {
294
294
vma_end_read(vma);
295
295
count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
296
-
tsk->thread.bad_cause = SEGV_ACCERR;
297
-
bad_area_nosemaphore(regs, code, addr);
296
+
tsk->thread.bad_cause = cause;
297
+
bad_area_nosemaphore(regs, SEGV_ACCERR, addr);
298
298
return;
299
299
}
300
300
+11
-10
arch/riscv/mm/init.c
+11
-10
arch/riscv/mm/init.c
···
250
250
kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
251
251
252
252
/*
253
-
* memblock allocator is not aware of the fact that last 4K bytes of
254
-
* the addressable memory can not be mapped because of IS_ERR_VALUE
255
-
* macro. Make sure that last 4k bytes are not usable by memblock
256
-
* if end of dram is equal to maximum addressable memory. For 64-bit
257
-
* kernel, this problem can't happen here as the end of the virtual
258
-
* address space is occupied by the kernel mapping then this check must
259
-
* be done as soon as the kernel mapping base address is determined.
253
+
* Reserve physical address space that would be mapped to virtual
254
+
* addresses greater than (void *)(-PAGE_SIZE) because:
255
+
* - This memory would overlap with ERR_PTR
256
+
* - This memory belongs to high memory, which is not supported
257
+
*
258
+
* This is not applicable to 64-bit kernel, because virtual addresses
259
+
* after (void *)(-PAGE_SIZE) are not linearly mapped: they are
260
+
* occupied by kernel mapping. Also it is unrealistic for high memory
261
+
* to exist on 64-bit platforms.
260
262
*/
261
263
if (!IS_ENABLED(CONFIG_64BIT)) {
262
-
max_mapped_addr = __pa(~(ulong)0);
263
-
if (max_mapped_addr == (phys_ram_end - 1))
264
-
memblock_set_current_limit(max_mapped_addr - 4096);
264
+
max_mapped_addr = __va_to_pa_nodebug(-PAGE_SIZE);
265
+
memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr);
265
266
}
266
267
267
268
min_low_pfn = PFN_UP(phys_ram_base);