main/musl: fix pthread_exit code to match kernel behavior

https://github.com/dotnet/coreclr/issues/5872

2 files changed, 74 insertions, 1 deletions

diff --git a/main/musl/APKBUILD b/main/musl/APKBUILD
index 9dfde814f5..cd5fe80969 100644
--- a/main/musl/APKBUILD
+++ b/main/musl/APKBUILD
@@ -2,7 +2,7 @@
 # Maintainer: Timo Teräs <timo.teras@iki.fi>
 pkgname=musl
 pkgver=1.1.14
-pkgrel=10
+pkgrel=11
 pkgdesc="the musl c library (libc) implementation"
 url="http://www.musl-libc.org/"
 arch="all"
@@ -25,6 +25,7 @@ source="http://www.musl-libc.org/releases/musl-$pkgver.tar.gz
 	0011-fix-FILE-buffer-underflow-in-ungetwc.patch
 	0012-fix-incorrect-protocol-name-and-number-for-egp.patch
 	0001-check-result-from-res_mkquery.patch
+	fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
 
 	ldconfig
 	__stack_chk_fail_local.c
@@ -145,6 +146,7 @@ a2457ce90f3e4d5ef04005b6f42e9bc3  0009-fix-regression-disabling-use-of-pause-ins
 1a54c766a86a56946ee53f9515410670  0011-fix-FILE-buffer-underflow-in-ungetwc.patch
 67ca785b787c53316397f96d21afab31  0012-fix-incorrect-protocol-name-and-number-for-egp.patch
 3e78b4c125b0c3f06c06a9b4ade8e18d  0001-check-result-from-res_mkquery.patch
+34e04b179e4b4a1fdedd27cd27455271  fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
 830d01f7821b978df770b06db3790921  ldconfig
 0df687757221bbb0fc1aa67f1bd646f9  __stack_chk_fail_local.c
 57ef2c63b9ec6a2041694ace97d4ffa2  getconf.c
@@ -164,6 +166,7 @@ b937311664b96b6272e4e62e1aa0d44edd58c825cbb95746c82fab85a6390968  0008-fix-undef
 b19de98d4c4051c2ff89b5f4b2705444f6f4c44a639692bedfa30a71b965fd04  0011-fix-FILE-buffer-underflow-in-ungetwc.patch
 8721a088af8aa388c771174eb8e9b19cc96c47fe07d2fa8c70a640cdb7d52221  0012-fix-incorrect-protocol-name-and-number-for-egp.patch
 7e5b08404da6f306ab8da9e81107a7901415d612069103d6f7b6b8e6ea504959  0001-check-result-from-res_mkquery.patch
+87e1b3398abf440b6757a61d40511714f8b97e1dfca09c406347842e885ff444  fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
 b4a2c06db38742e8c42c3c9838b285a7d8cdac6c091ff3df5ff9a15f1e41b9c7  ldconfig
 299a7d75a09de3e2e11e7fb4acc3182e4a14e868093d2f30938fce9bfcff13da  __stack_chk_fail_local.c
 d87d0cbb3690ae2c5d8cc218349fd8278b93855dd625deaf7ae50e320aad247c  getconf.c
@@ -183,6 +186,7 @@ c0cf860bc7c6259dc626a1178258010e4ea6588f1ecd6c6c69ed85f11c5f0f6c502f59af3d9655bb
 93a696ef060f4a7c9efe32589e3f8e0bb08cbbae6d0f9852aef8555f2f095f0d50431f55647ee8b59599916b0c90bb4aa251be495d3d2697b36c7cad5c9375a4  0011-fix-FILE-buffer-underflow-in-ungetwc.patch
 78f1952b786cd4c31d956e169a6362d0f3007d68cb95308f88ae556dac88689cfa0e94856e5e8f727b1f27a9df5b35dab0fec8f3df4d925207c4980eb4e9f80f  0012-fix-incorrect-protocol-name-and-number-for-egp.patch
 d1e393976546216a6de28b00a5b405a14d2cdf71945b695c3b45cd636f213ad037108f42301f21f213dbdac4dbce977813aea62cf9cee9f74432e1475e11ce22  0001-check-result-from-res_mkquery.patch
+b3d62e1dc83586c5babd68491dc6d0c8022b4bc234cdaf45726a0ebe35ce32ec85a39a69949bffa37110f0a4d8af8c9ecc5c1e9d76a0b131f20e6013a43feff3  fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
 8d3a2d5315fc56fee7da9abb8b89bb38c6046c33d154c10d168fb35bfde6b0cf9f13042a3bceee34daf091bc409d699223735dcf19f382eeee1f6be34154f26f  ldconfig
 062bb49fa54839010acd4af113e20f7263dde1c8a2ca359b5fb2661ef9ed9d84a0f7c3bc10c25dcfa10bb3c5a4874588dff636ac43d5dbb3d748d75400756d0b  __stack_chk_fail_local.c
 0d80f37b34a35e3d14b012257c50862dfeb9d2c81139ea2dfa101d981d093b009b9fa450ba27a708ac59377a48626971dfc58e20a3799084a65777a0c32cbc7d  getconf.c
diff --git a/main/musl/fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch b/main/musl/fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
new file mode 100644
index 0000000000..445fa80455
--- /dev/null
+++ b/main/musl/fix-failure-to-obtain-EOWNERDEAD-status-for-process-shared-robust-mutexes.patch
@@ -0,0 +1,69 @@
+commit 384d103d94dba0472a587861f67d7ed6e8955f86
+Author: Rich Felker <dalias@aerifal.cx>
+Date:   Mon Jun 27 15:18:13 2016 -0400
+
+    fix failure to obtain EOWNERDEAD status for process-shared robust mutexes
+    
+    Linux's documentation (robust-futex-ABI.txt) claims that, when a
+    process dies with a futex on the robust list, bit 30 (0x40000000) is
+    set to indicate the status. however, what actually happens is that
+    bits 0-30 are replaced with the value 0x40000000, i.e. bits 0-29
+    (containing the old owner tid) are cleared at the same time bit 30 is
+    set.
+    
+    our userspace-side code for robust mutexes was written based on that
+    documentation, assuming that kernel would never produce a futex value
+    of 0x40000000, since the low (owner) bits would always be non-zero.
+    commit d338b506e39b1e2c68366b12be90704c635602ce introduced this
+    assumption explicitly while fixing another bug in how non-recoverable
+    status for robust mutexes was tracked. presumably the tests conducted
+    at that time only checked non-process-shared robust mutexes, which are
+    handled in pthread_exit (which implemented the documented kernel
+    protocol, not the actual one) rather than by the kernel.
+    
+    change pthread_exit robust list processing to match the kernel
+    behavior, clearing bits 0-29 while setting bit 30, and use the value
+    0x7fffffff instead of 0x40000000 to encode non-recoverable status. the
+    choice of value here is arbitrary; any value with at least one of bits
+    0-29 set should work just as well,
+
+diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
+index e7df34a..9f6b98e 100644
+--- a/src/thread/pthread_create.c
++++ b/src/thread/pthread_create.c
+@@ -79,7 +79,7 @@ _Noreturn void __pthread_exit(void *result)
+ 		int priv = (m->_m_type & 128) ^ 128;
+ 		self->robust_list.pending = rp;
+ 		self->robust_list.head = *rp;
+-		int cont = a_swap(&m->_m_lock, self->tid|0x40000000);
++		int cont = a_swap(&m->_m_lock, 0x40000000);
+ 		self->robust_list.pending = 0;
+ 		if (cont < 0 || waiters)
+ 			__wake(&m->_m_lock, 1, priv);
+diff --git a/src/thread/pthread_mutex_trylock.c b/src/thread/pthread_mutex_trylock.c
+index 0df3ce2..54876a6 100644
+--- a/src/thread/pthread_mutex_trylock.c
++++ b/src/thread/pthread_mutex_trylock.c
+@@ -14,7 +14,7 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m)
+ 		m->_m_count++;
+ 		return 0;
+ 	}
+-	if (own == 0x40000000) return ENOTRECOVERABLE;
++	if (own == 0x7fffffff) return ENOTRECOVERABLE;
+ 
+ 	if (m->_m_type & 128) {
+ 		if (!self->robust_list.off) {
+diff --git a/src/thread/pthread_mutex_unlock.c b/src/thread/pthread_mutex_unlock.c
+index 02da92a..7dd00d2 100644
+--- a/src/thread/pthread_mutex_unlock.c
++++ b/src/thread/pthread_mutex_unlock.c
+@@ -24,7 +24,7 @@ int __pthread_mutex_unlock(pthread_mutex_t *m)
+ 		if (next != &self->robust_list.head) *(volatile void *volatile *)
+ 			((char *)next - sizeof(void *)) = prev;
+ 	}
+-	cont = a_swap(&m->_m_lock, (type & 8) ? 0x40000000 : 0);
++	cont = a_swap(&m->_m_lock, (type & 8) ? 0x7fffffff : 0);
+ 	if (type != PTHREAD_MUTEX_NORMAL && !priv) {
+ 		self->robust_list.pending = 0;
+ 		__vm_unlock();
+