From: Mike Rapoport <rppt@xxxxxxxxxxxxx> The __nocache_fix(VADDR) macro is used to add an offset for pointers and its "return type" is 'void *'. We can do better and keep the type information with simply by casting the return value to (__typeof__(VADDR)). This will ".. show when those pgd/p4d/pud pointers get mis-used because they don't end up dropping the type info.." The addition of the casting to __nocache_fix() also allows to remove explicit casts at its call sites. Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/stablestablestablestablestabler/CAHk-=wisORTa7QVPnFqNw9pFs62UiwgsD4C4d=MtYy1o4JPyGQ@xxxxxxxxxxxxxx --- arch/sparc/include/asm/pgtsrmmu.h | 2 +- arch/sparc/mm/srmmu.c | 16 ++++++++-------- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/sparc/include/asm/pgtsrmmu.h b/arch/sparc/include/asm/pgtsrmmu.h index 32a508897501..941d42a59b81 100644 --- a/arch/sparc/include/asm/pgtsrmmu.h +++ b/arch/sparc/include/asm/pgtsrmmu.h @@ -143,7 +143,7 @@ extern unsigned long last_valid_pfn; extern void *srmmu_nocache_pool; #define __nocache_pa(VADDR) (((unsigned long)VADDR) - SRMMU_NOCACHE_VADDR + __pa((unsigned long)srmmu_nocache_pool)) #define __nocache_va(PADDR) (__va((unsigned long)PADDR) - (unsigned long)srmmu_nocache_pool + SRMMU_NOCACHE_VADDR) -#define __nocache_fix(VADDR) __va(__nocache_pa(VADDR)) +#define __nocache_fix(VADDR) ((__typeof__(VADDR))__va(__nocache_pa(VADDR))) /* Accessing the MMU control register. */ unsigned int srmmu_get_mmureg(void); diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c index dbf5334dd084..d86e6c657922 100644 --- a/arch/sparc/mm/srmmu.c +++ b/arch/sparc/mm/srmmu.c @@ -724,7 +724,7 @@ static void __init srmmu_early_allocate_ptable_skeleton(unsigned long start, pud_set(__nocache_fix(pudp), pmdp); } pmdp = pmd_offset(__nocache_fix(pudp), start); - if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) { + if (srmmu_pmd_none(*__nocache_fix(pmdp))) { ptep = __srmmu_get_nocache(PTE_SIZE, PTE_SIZE); if (ptep == NULL) early_pgtable_allocfail("pte"); @@ -836,11 +836,11 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, p4dp = p4d_offset(pgdp, start); pudp = pud_offset(p4dp, start); if (what == 2) { - *(pgd_t *)__nocache_fix(pgdp) = __pgd(probed); + *__nocache_fix(pgdp) = __pgd(probed); start += SRMMU_PGDIR_SIZE; continue; } - if (pud_none(*(pud_t *)__nocache_fix(pudp))) { + if (pud_none(*__nocache_fix(pudp))) { pmdp = __srmmu_get_nocache(SRMMU_PMD_TABLE_SIZE, SRMMU_PMD_TABLE_SIZE); if (pmdp == NULL) @@ -849,7 +849,7 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, pud_set(__nocache_fix(pudp), pmdp); } pmdp = pmd_offset(__nocache_fix(pudp), start); - if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) { + if (srmmu_pmd_none(*__nocache_fix(pmdp))) { ptep = __srmmu_get_nocache(PTE_SIZE, PTE_SIZE); if (ptep == NULL) early_pgtable_allocfail("pte"); @@ -865,12 +865,12 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, unsigned long *val; x = (start >> PMD_SHIFT) & 15; val = &pmdp->pmdv[x]; - *(unsigned long *)__nocache_fix(val) = probed; + *__nocache_fix(val) = probed; start += SRMMU_REAL_PMD_SIZE; continue; } ptep = pte_offset_kernel(__nocache_fix(pmdp), start); - *(pte_t *)__nocache_fix(ptep) = __pte(probed); + *__nocache_fix(ptep) = __pte(probed); start += PAGE_SIZE; } } @@ -884,7 +884,7 @@ static void __init do_large_mapping(unsigned long vaddr, unsigned long phys_base unsigned long big_pte; big_pte = KERNEL_PTE(phys_base >> 4); - *(pgd_t *)__nocache_fix(pgdp) = __pgd(big_pte); + *__nocache_fix(pgdp) = __pgd(big_pte); } /* Map sp_bank entry SP_ENTRY, starting at virtual address VBASE. */ @@ -974,7 +974,7 @@ void __init srmmu_paging_init(void) srmmu_ctx_table_phys = (ctxd_t *)__nocache_pa(srmmu_context_table); for (i = 0; i < num_contexts; i++) - srmmu_ctxd_set((ctxd_t *)__nocache_fix(&srmmu_context_table[i]), srmmu_swapper_pg_dir); + srmmu_ctxd_set(__nocache_fix(&srmmu_context_table[i]), srmmu_swapper_pg_dir); flush_cache_all(); srmmu_set_ctable_ptr((unsigned long)srmmu_ctx_table_phys); -- 2.26.2
