Christophe Leroy <christophe.le...@csgroup.eu> writes: > 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.le...@csgroup.eu> > --- > arch/powerpc/include/asm/book3s/64/hash.h | 2 +- > arch/powerpc/mm/book3s64/hash_utils.c | 3 ++- > arch/powerpc/mm/pageattr.c | 10 +++++++--- > 3 files changed, 10 insertions(+), 5 deletions(-) > ... > diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c > index 16b8d20d6ca8..62b678585878 100644 > --- a/arch/powerpc/mm/pageattr.c > +++ b/arch/powerpc/mm/pageattr.c > @@ -106,17 +106,21 @@ 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: set_memory_%sp() failed\n", enable ? "" : "n");
This doesn't compile, it's missing __func__ I guess. Seems like we could keep it simpler though, it should hopefully never happen anyway, eg: panic("%s: changing memory protections failed\n", __func__); cheers