On 4/10/21 11:23 PM, Lu Baolu wrote:
> Commit f68c7f539b6e9 ("iommu/vt-d: Enable write protect for supervisor
> SVM") added pasid_enable_wpe() which hit below compile error with !X86.
>
> ../drivers/iommu/intel/pasid.c: In function 'pasid_enable_wpe':
> ../drivers/iommu/intel/pasid.c:554:22: error: implicit declaration of
> function 'read_cr0' [-Werror=implicit-function-declaration]
> 554 | unsigned long cr0 = read_cr0();
> | ^~~~~~~~
> In file included from ../include/linux/build_bug.h:5,
> from ../include/linux/bits.h:22,
> from ../include/linux/bitops.h:6,
> from ../drivers/iommu/intel/pasid.c:12:
> ../drivers/iommu/intel/pasid.c:557:23: error: 'X86_CR0_WP' undeclared (first
> use in this function)
> 557 | if (unlikely(!(cr0 & X86_CR0_WP))) {
> | ^~~~~~~~~~
> ../include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
> 78 | # define unlikely(x) __builtin_expect(!!(x), 0)
> | ^
> ../drivers/iommu/intel/pasid.c:557:23: note: each undeclared identifier is
> reported only once for each function it appears in
> 557 | if (unlikely(!(cr0 & X86_CR0_WP))) {
> | ^~~~~~~~~~
> ../include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
> 78 | # define unlikely(x) __builtin_expect(!!(x), 0)
> |
>
> Add the missing dependency.
>
> Cc: Sanjay Kumar <sanjay.k.ku...@intel.com>
> Cc: Jacob Pan <jacob.jun....@linux.intel.com>
> Cc: Randy Dunlap <rdun...@infradead.org>
> Reported-by: kernel test robot <l...@intel.com>
> Reported-by: Randy Dunlap <rdun...@infradead.org>
> Fixes: f68c7f539b6e9 ("iommu/vt-d: Enable write protect for supervisor SVM")
> Signed-off-by: Lu Baolu <baolu...@linux.intel.com>
Acked-by: Randy Dunlap <rdun...@infradead.org> # build-tested
Thanks.
> ---
> drivers/iommu/intel/pasid.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
> index 477b2e1d303c..72646bafc52f 100644
> --- a/drivers/iommu/intel/pasid.c
> +++ b/drivers/iommu/intel/pasid.c
> @@ -551,6 +551,7 @@ static void pasid_flush_caches(struct intel_iommu *iommu,
>
> static inline int pasid_enable_wpe(struct pasid_entry *pte)
> {
> +#ifdef CONFIG_X86
> unsigned long cr0 = read_cr0();
>
> /* CR0.WP is normally set but just to be sure */
> @@ -558,6 +559,7 @@ static inline int pasid_enable_wpe(struct pasid_entry
> *pte)
> pr_err_ratelimited("No CPU write protect!\n");
> return -EINVAL;
> }
> +#endif
> pasid_set_wpe(pte);
>
> return 0;
>
--
~Randy
