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The problem is even if it is NULL it will be  try to derefrence it. Which might lead to segmentation fault. > >> Since xe_lmtt_init ensures lmtt->ops is populated >> remove the check. > With this in mind we could simply remove all the asserts in the code. > > I believe that if someone introduced it here it is likely because > during some development or refactor this ended up being a problem > and want some earlier kind of warning with backtrace information. > >> Reported by static analyzer. > Perhaps then replace with an > if (!lmtt->ops) { > drm_WARN(...); > return; > } I am also of the opinion that this is the correct check to have instead of just warning about lmtt->ops being NULL and continue to dereference it. Need clarity on what should we return in case of lmtt->ops being NULL since expected return type is u64. > > and/or mark the tool as a false positive?! > >> Cc: Rodrigo Vivi >> Signed-off-by: Himal Prasad Ghimiray >> --- >> drivers/gpu/drm/xe/xe_lmtt.c | 1 - >> 1 file changed, 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/xe/xe_lmtt.c b/drivers/gpu/drm/xe/xe_lmtt.c >> index 0d7c5514e092..d6d75414bb99 100644 >> --- a/drivers/gpu/drm/xe/xe_lmtt.c >> +++ b/drivers/gpu/drm/xe/xe_lmtt.c >> @@ -487,7 +487,6 @@ u64 xe_lmtt_estimate_pt_size(struct xe_lmtt *lmtt, u64 size) >> >> lmtt_assert(lmtt, IS_SRIOV_PF(lmtt_to_xe(lmtt))); >> lmtt_assert(lmtt, IS_DGFX(lmtt_to_xe(lmtt))); >> - lmtt_assert(lmtt, lmtt->ops); >> >> pt_size = PAGE_ALIGN(lmtt->ops->lmtt_pte_size(level) * >> lmtt->ops->lmtt_pte_num(level)); >> -- >> 2.25.1 >>