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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 913224001E X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: 6bespwogrmighz4nds9f71xxzghhw6at X-HE-Tag: 1714540245-934540 X-HE-Meta: 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 F2px2Bir HXasHVROpwj33+7S0jJzoJFK8lRqg2wXZp+Jq0f3K3vWWBXrYunyrSzF0w/DZ3gBYJqltgNRpovaDjvXQy1B8sMTFy+w6tFwpAoCieNGVfaYzE2RxPNM9lZhDI+5dVPvpWJw58f3jfhAscDxiiD1A8JEiS9Hbp/x5I3RGHFQffhsDIA3TMl4KzE3QQk2zio+cWfN550zXIeXohbr87jvgDXPjLSJU0Spz0FPAD+0ecmyhcXKq9UBWBSofsLacYfO2kl6tgZUg1T0RDOnTFUr4HlxO/Yqsyc28kcwgHaF/t2svPgFFDbXBeCfxixdlnx4Xh0NjKRbZEYBaawuESBGk711PMlFAWT+/FRtyKGOEPyUgPl+hkQgLYmo+IWfJXDi9FuQBynxHsR7iIPSrt+dX85TKuQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > + pinned = -ENOMEM; > + int attempts = 0; > + /* > + * pin_user_pages_fast() can return -EAGAIN, due to falling back > + * to gup-slow and then failing to migrate pages out of > + * ZONE_MOVABLE due to a transient elevated page refcount. > + * > + * One retry is enough to avoid this problem, so far, but let's > + * use a slightly higher retry count just in case even larger > + * systems have a longer-lasting transient refcount problem. > + * > + */ > + static const int MAX_ATTEMPTS = 3; > + > + while (pinned == -EAGAIN && attempts < MAX_ATTEMPTS) { > + pinned = pin_user_pages_fast(cur_base, > + min_t(unsigned long, > + npages, PAGE_SIZE / > + sizeof(struct page *)), > + gup_flags, page_list); > ret = pinned; > - goto umem_release; > + attempts++; > + > + if (pinned == -EAGAIN) > + continue; > } > + if (pinned < 0) > + goto umem_release; This doesn't make sense. IFF a blind retry is all that is needed it should be done in the core functionality. I fear it's not that easy, though.