In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
gve: fix Rx queue stall on alloc failure<\/p>\n
When the system is under extreme memory pressure, page allocations can
\nfail during the Rx buffer refill loop. If the number of buffers posted
\nto hardware falls below a critical low threshold and the refill loop
\nexits due to allocation failures, the queue can stall:<\/p>\n
1. The device drops incoming packets because there are no descriptors.
\n2. Since no packets are processed, no Rx completions are generated.
\n3. Because no completions occur, NAPI is never scheduled, preventing
\n the refill loop from running again even after memory is freed.<\/p>\n
This results in a permanent queue stall.<\/p>\n
Resolve this by introducing a starvation recovery timer for each Rx queue.
\nIf the number of buffers posted to hardware falls below a critical low
\nthreshold, start a timer to periodically reschedule NAPI. Once NAPI runs
\nand successfully refills the queue above the threshold, the timer is
\nnot rescheduled.<\/p>\n
The threshold is set to 32 because a single maximum-sized Receive Segment
\nCoalescing (RSC) packet can consume up to 19 descriptors in the Rx path.
\nLower thresholds (such as 8 or 16) would be insufficient to process a
\ncomplete maximum-sized RSC packet, risking packet drops or unexpected
\nhardware behavior under memory pressure. Setting the threshold to 32
\nguarantees a safe margin to handle at least one full RSC packet.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
gve: fix Rx queue stall on alloc failure<\/p>\n
When the system is under extreme memory pressure, page allocations can
\nfail during the Rx<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-5341","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/5341","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5341"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5341"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5341"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}