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authorDan Goodliffe <dan.goodliffe@octal.co.uk>2022-02-21 09:39:43 +0000
committerDan Goodliffe <dan.goodliffe@octal.co.uk>2022-02-21 09:39:43 +0000
commit9a42bd6998537c99162af4010ada69ba1c655ea7 (patch)
tree25de17df72b5b75ee9e0e64dd30fa78eb41af605
parentUpstream HA Proxy segfault fix (diff)
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Revert "Upstream HA Proxy segfault fix"
This reverts commit 113fb5b22b06ff455d3ad842d517aadf1566fa89.
-rw-r--r--net-proxy/haproxy/ecc473b5299ccd0007a73ec4b4af099ac65e9c43.patch132
1 files changed, 0 insertions, 132 deletions
diff --git a/net-proxy/haproxy/ecc473b5299ccd0007a73ec4b4af099ac65e9c43.patch b/net-proxy/haproxy/ecc473b5299ccd0007a73ec4b4af099ac65e9c43.patch
deleted file mode 100644
index 19acb57..0000000
--- a/net-proxy/haproxy/ecc473b5299ccd0007a73ec4b4af099ac65e9c43.patch
+++ /dev/null
@@ -1,132 +0,0 @@
-From ecc473b5299ccd0007a73ec4b4af099ac65e9c43 Mon Sep 17 00:00:00 2001
-From: Willy Tarreau <w@1wt.eu>
-Date: Thu, 27 Jan 2022 15:46:19 +0100
-Subject: [PATCH] BUG/MAJOR: compiler: relax alignment constraints on certain
- structures
-
-In github bug #1517, Mike Lothian reported instant crashes on startup
-on RHEL8 + gcc-11 that appeared with 2.4 when allocating a proxy.
-
-The analysis brought us down to the THREAD_ALIGN() entries that were
-placed inside the "server" struct to avoid false sharing of cache lines.
-It turns out that some modern gcc make use of aligned vector operations
-to manipulate some fields (e.g. memset() etc) and that these structures
-allocated using malloc() are not necessarily aligned, hence the crash.
-
-The compiler is allowed to do that because the structure claims to be
-aligned. The problem is in fact that the alignment propagates to other
-structures that embed it. While most of these structures are used as
-statically allocated variables, some are dynamic and cannot use that.
-A deeper analysis showed that struct server does this, propagates to
-struct proxy, which propagates to struct spoe_config, all of which
-are allocated using malloc/calloc.
-
-A better approach would consist in usins posix_memalign(), but this one
-is not available everywhere and will either need to be reimplemented
-less efficiently (by always wasting 64 bytes before the area), or a
-few functions will have to be specifically written to deal with the
-few structures that are dynamically allocated.
-
-But the deeper problem that remains is that it is difficult to track
-structure alignment, as there's no available warning to check this.
-For the long term we'll probably have to create a macro such as
-"struct_malloc()" etc which takes a type and enforces an alignment
-based on the one of this type. This also means propagating that to
-pools as well, and it's not a tiny task.
-
-For now, let's get rid of the forced alignment in struct server, and
-replace it with extra padding. By punching 63-byte holes, we can keep
-areas on separate cache lines. Doing so moderately increases the size
-of the "server" structure (~+6%) but that's the best short-term option
-and it's easily backportable.
-
-This will have to be backported as far as 2.4.
-
-Thanks to Mike for the detailed report.
----
- include/haproxy/compiler.h | 25 +++++++++++++++++++++++++
- include/haproxy/server-t.h | 8 ++++----
- 2 files changed, 29 insertions(+), 4 deletions(-)
-
-diff --git a/include/haproxy/compiler.h b/include/haproxy/compiler.h
-index f18b5fa5cd..3943fe6459 100644
---- a/include/haproxy/compiler.h
-+++ b/include/haproxy/compiler.h
-@@ -220,6 +220,17 @@
- #define HA_HAVE_CAS_DW
- #endif
-
-+/*********************** IMPORTANT NOTE ABOUT ALIGNMENT **********************\
-+ * Alignment works fine for variables. It also works on types and struct *
-+ * members by propagating the alignment to the container struct itself, *
-+ * but this requires that variables of the affected type are properly *
-+ * aligned themselves. While regular variables will always abide, those *
-+ * allocated using malloc() will not! Most platforms provide posix_memalign()*
-+ * for this, but it's not available everywhere. As such one ought not to use *
-+ * these alignment declarations inside structures that are dynamically *
-+ * allocated. If the purpose is only to avoid false sharing of cache lines *
-+ * for multi_threading, see THREAD_PAD() below. *
-+\*****************************************************************************/
-
- /* sets alignment for current field or variable */
- #ifndef ALIGNED
-@@ -294,6 +305,20 @@
- #endif
- #endif
-
-+/* add optional padding of the specified size between fields in a structure,
-+ * only when threads are enabled. This is used to avoid false sharing of cache
-+ * lines for dynamically allocated structures which cannot guarantee alignment.
-+ */
-+#ifndef THREAD_PAD
-+# ifdef USE_THREAD
-+# define __THREAD_PAD(x,l) char __pad_##l[x]
-+# define _THREAD_PAD(x,l) __THREAD_PAD(x, l)
-+# define THREAD_PAD(x) _THREAD_PAD(x, __LINE__)
-+# else
-+# define THREAD_PAD(x)
-+# endif
-+#endif
-+
- /* The THREAD_LOCAL type attribute defines thread-local storage and is defined
- * to __thread when threads are enabled or empty when disabled.
- */
-diff --git a/include/haproxy/server-t.h b/include/haproxy/server-t.h
-index 09f39333d6..e53d6121b4 100644
---- a/include/haproxy/server-t.h
-+++ b/include/haproxy/server-t.h
-@@ -273,7 +273,7 @@ struct server {
- /* The elements below may be changed on every single request by any
- * thread, and generally at the same time.
- */
-- ALWAYS_ALIGN(64);
-+ THREAD_PAD(63);
- struct eb32_node idle_node; /* When to next do cleanup in the idle connections */
- unsigned int curr_idle_conns; /* Current number of orphan idling connections, both the idle and the safe lists */
- unsigned int curr_idle_nb; /* Current number of connections in the idle list */
-@@ -288,14 +288,14 @@ struct server {
- /* Element below are usd by LB algorithms and must be doable in
- * parallel to other threads reusing connections above.
- */
-- ALWAYS_ALIGN(64);
-+ THREAD_PAD(63);
- __decl_thread(HA_SPINLOCK_T lock); /* may enclose the proxy's lock, must not be taken under */
- unsigned npos, lpos; /* next and last positions in the LB tree, protected by LB lock */
- struct eb32_node lb_node; /* node used for tree-based load balancing */
- struct server *next_full; /* next server in the temporary full list */
-
- /* usually atomically updated by any thread during parsing or on end of request */
-- ALWAYS_ALIGN(64);
-+ THREAD_PAD(63);
- int cur_sess; /* number of currently active sessions (including syn_sent) */
- int served; /* # of active sessions currently being served (ie not pending) */
- int consecutive_errors; /* current number of consecutive errors */
-@@ -303,7 +303,7 @@ struct server {
- struct be_counters counters; /* statistics counters */
-
- /* Below are some relatively stable settings, only changed under the lock */
-- ALWAYS_ALIGN(64);
-+ THREAD_PAD(63);
-
- struct eb_root *lb_tree; /* we want to know in what tree the server is */
- struct tree_occ *lb_nodes; /* lb_nodes_tot * struct tree_occ */