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>> 12885cbe88ddf6 Baolin Wang 2024-08-12 2171 goto unlock; >> >> Imagine we hit this goto on the first iteration > > That can happen (but if it does, we set -EEXIST in the xa_state). > >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2213 unlock: >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2214 xas_unlock_irq(&xas); >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2215 >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2216 if (!xas_nomem(&xas, gf= p)) >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2217 break; >> >> And we hit this break. > > That's guaranteed. If there's an errno in the xa_state that isn't > -ENOMEM, xas_nomem() will fail. > >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2218 } >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2219 >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2220 if (xas_error(&xas)) >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2221 return xas_error(&xas);= >> 12885cbe88ddf6 Baolin Wang 2024-08-12 2222 >> d53c78fffe7ad3 Zi Yan 2025-03-14 @2223 return entry_order; > > but if this does happen, then xas_error() will be true and we'll return= > -EEXIST here instead of returning entry_order. Hi Matthew, Thank you for the explanation. Hi Dan, I got a similar report 3 months ago and explained it already. See https://lore.kernel.org/linux-mm/B024C29C-96D4-4F92-B2EF-F01CB06B27DF= @nvidia.com/ Best Regards, Yan, Zi