Mercurial > hg > nginx
view auto/init @ 7969:84c60a3cd12a stable-1.20
Changed ngx_chain_update_chains() to test tag first (ticket #2248).
Without this change, aio used with HTTP/2 can result in connection hang,
as observed with "aio threads; aio_write on;" and proxying (ticket #2248).
The problem is that HTTP/2 updates buffers outside of the output filters
(notably, marks them as sent), and then posts a write event to call
output filters. If a filter does not call the next one for some reason
(for example, because of an AIO operation in progress), this might
result in a state when the owner of a buffer already called
ngx_chain_update_chains() and can reuse the buffer, while the same buffer
is still sitting in the busy chain of some other filter.
In the particular case a buffer was sitting in output chain's ctx->busy,
and was reused by event pipe. Output chain's ctx->busy was permanently
blocked by it, and this resulted in connection hang.
Fix is to change ngx_chain_update_chains() to skip buffers from other
modules unconditionally, without trying to wait for these buffers to
become empty.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Sat, 30 Oct 2021 02:39:19 +0300 |
parents | 549b13cd793b |
children |
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# Copyright (C) Igor Sysoev # Copyright (C) Nginx, Inc. NGX_MAKEFILE=$NGX_OBJS/Makefile NGX_MODULES_C=$NGX_OBJS/ngx_modules.c NGX_AUTO_HEADERS_H=$NGX_OBJS/ngx_auto_headers.h NGX_AUTO_CONFIG_H=$NGX_OBJS/ngx_auto_config.h NGX_AUTOTEST=$NGX_OBJS/autotest NGX_AUTOCONF_ERR=$NGX_OBJS/autoconf.err # STUBs NGX_ERR=$NGX_OBJS/autoconf.err MAKEFILE=$NGX_OBJS/Makefile NGX_PCH= NGX_USE_PCH= # check the echo's "-n" option and "\c" capability if echo "test\c" | grep c >/dev/null; then if echo -n test | grep n >/dev/null; then ngx_n= ngx_c= else ngx_n=-n ngx_c= fi else ngx_n= ngx_c='\c' fi # create Makefile cat << END > Makefile default: build clean: rm -rf Makefile $NGX_OBJS .PHONY: default clean END