On Mon, Jan 16, 2023 at 09:05:08AM -0500, Sasha Levin wrote:
From: Will Deacon will@kernel.org
[ Upstream commit 4e4ff23a35ee3a145fbc8378ecfeaab2d235cddd ]
With only two levels of page-table, the generic 'pud_*' macros are implemented using dummy operations in pgtable-nopmd.h. Since commit 730a11f982e6 ("arm64/mm: add pud_user_exec() check in pud_user_accessible_page()"), pud_user_accessible_page() unconditionally calls pud_user_exec(), which is an arm64-specific helper and therefore isn't defined by pgtable-nopmd.h. This results in a build failure for configurations with only two levels of page table:
arch/arm64/include/asm/pgtable.h: In function 'pud_user_accessible_page':
arch/arm64/include/asm/pgtable.h:870:51: error: implicit declaration of function 'pud_user_exec'; did you mean 'pmd_user_exec'? [-Werror=implicit-function-declaration]
870 | return pud_leaf(pud) && (pud_user(pud) || pud_user_exec(pud)); | ^~~~~~~~~~~~~ | pmd_user_execFix the problem by defining pud_user_exec() as pud_user() in this case.
Link: https://lore.kernel.org/r/202301080515.z6zEksU4-lkp@intel.com Reported-by: kernel test robot lkp@intel.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org
I don't think this patch should be backported to 5.4. It is a fix for a commit that went in shortly before this one (730a11f982e6). The latter commit does have a Fixes tag but I guess Will thought it's not worth a cc stable (and it's up to 5.19 anyway).