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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2024-02-16 11:17:34 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2024-03-03 12:18:45 +0100 |
| commit | 9cbacb834b4afcb55eb8ac5115fa82fc7ede5c83 (patch) | |
| tree | ecc655227ddf3507515e9aea2664c8605564c524 | |
| parent | powerpc: Refactor __kernel_map_pages() (diff) | |
| download | linux-9cbacb834b4afcb55eb8ac5115fa82fc7ede5c83.tar.xz linux-9cbacb834b4afcb55eb8ac5115fa82fc7ede5c83.zip | |
powerpc: Don't ignore errors from set_memory_{n}p() in __kernel_map_pages()
set_memory_p() and set_memory_np() can fail.
As mentioned in linux/mm.h:
/*
* To support DEBUG_PAGEALLOC architecture must ensure that
* __kernel_map_pages() never fails
*/
So panic in case set_memory_p() or set_memory_np() fail
in __kernel_map_pages().
Link: https://github.com/KSPP/linux/issues/7
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20ef75884aa6a636e8298736f3d1056b0793d3d9.1708078640.git.christophe.leroy@csgroup.eu
| -rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_decl.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/mm/pageattr.c | 10 |
3 files changed, 10 insertions, 5 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 0626a25b0d72..01c3b4b65241 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -2172,7 +2172,7 @@ static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) mmu_kernel_ssize, 0); } -void hash__kernel_map_pages(struct page *page, int numpages, int enable) +int hash__kernel_map_pages(struct page *page, int numpages, int enable) { unsigned long flags, vaddr, lmi; int i; @@ -2189,6 +2189,7 @@ void hash__kernel_map_pages(struct page *page, int numpages, int enable) kernel_unmap_linear_page(vaddr, lmi); } local_irq_restore(flags); + return 0; } #endif /* CONFIG_DEBUG_PAGEALLOC || CONFIG_KFENCE */ diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index 4eb62bb51d49..b4b662a61485 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -187,4 +187,4 @@ int create_section_mapping(unsigned long start, unsigned long end, int nid, pgprot_t prot); #endif -void hash__kernel_map_pages(struct page *page, int numpages, int enable); +int hash__kernel_map_pages(struct page *page, int numpages, int enable); diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c index 8a9d24218b74..ac22bf28086f 100644 --- a/arch/powerpc/mm/pageattr.c +++ b/arch/powerpc/mm/pageattr.c @@ -107,17 +107,21 @@ int change_memory_attr(unsigned long addr, int numpages, long action) #ifdef CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC void __kernel_map_pages(struct page *page, int numpages, int enable) { + int err; unsigned long addr = (unsigned long)page_address(page); if (PageHighMem(page)) return; if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && !radix_enabled()) - hash__kernel_map_pages(page, numpages, enable); + err = hash__kernel_map_pages(page, numpages, enable); else if (enable) - set_memory_p(addr, numpages); + err = set_memory_p(addr, numpages); else - set_memory_np(addr, numpages); + err = set_memory_np(addr, numpages); + + if (err) + panic("%s: changing memory protections failed\n", __func__); } #endif #endif |