commit 237b6067c17ac3ef1e02632b77deefb5e9837cbb [browse]
Author: Andrew Bonventre
Date: 2020-05-14 14:13:47 -04:00

[release-branch.go1.13] go1.13.11

Change-Id: I6fb5fbb3caf64e7d33412be4893edf8564e3a4de
Reviewed-on: https://go-review.googlesource.com/c/go/+/234001
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

commit 6b974e2bd3197bf6ff2245f5b24c0fccef352903 [browse]
Author: Michael Munday
Date: 2020-04-14 15:46:26 +01:00

[release-branch.go1.13] cmd/compile: fix deallocation of live value copies in regalloc

When deallocating the input register to a phi so that the phi
itself could be allocated to that register the code was also
deallocating all copies of that phi input value. Those copies
of the value could still be live and if they were the register
allocator could reuse them incorrectly to hold speculative
copies of other phi inputs. This causes strange bugs.

No test because this is a very obscure scenario that is hard
to replicate but CL 228060 adds an assertion to the compiler
that does trigger when running the std tests on linux/s390x
without this CL applied. Hopefully that assertion will prevent
future regressions.

Fixes #38442.

Change-Id: Id975dadedd731c7bb21933b9ea6b17daaa5c9e1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/228061
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
(cherry picked from commit 382fe3e2498f2066400e7e7007aa9903440e339d)
Reviewed-on: https://go-review.googlesource.com/c/go/+/230358

commit a57f07aac237d366630e85d080ef1ce0c34f0d09 [browse]
Author: Andrew Bonventre
Date: 2020-04-08 13:55:51 -04:00

[release-branch.go1.13] go1.13.10

Change-Id: I1ed1bc6652724d2e365f89de802c79ecc5c2660d
Reviewed-on: https://go-review.googlesource.com/c/go/+/227639
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>

commit 3a275aab75e40735c6c0184c1a61d4db0016d0a7 [browse]
Author: Austin Clements
Date: 2020-02-26 15:12:33 -05:00

[release-branch.go1.13] runtime: fix rounding in materializeGCProg

materializeGCProg allocates a temporary buffer for unrolling a GC
program. Unfortunately, when computing the size of the buffer, it
rounds *down* the number of bytes needed to store bitmap before
rounding up the number of pages needed to store those bytes. The fact
that it rounds up to pages usually mitigates the rounding down, but
the type from #37470 exists right on the boundary where this doesn't
work:

type Sequencer struct {
	htable [1 << 17]uint32
	buf    []byte
}

On 64-bit, this GC bitmap is exactly 8 KiB of zeros, followed by three
one bits. Hence, this needs 8193 bytes of storage, but the current
math in materializeGCProg rounds *down* the three one bits to 8192
bytes. Since this is exactly pageSize, the next step of rounding up to
the page size doesn't mitigate this error, and materializeGCProg
allocates a buffer that is one byte too small. runGCProg then writes
one byte past the end of this buffer, causing either a segfault (if
you're lucky!) or memory corruption.

Updates #37470.
Fixes #37483.

Change-Id: Iad24c463c501cd9b1dc1924bc2ad007991a094a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/224418
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

commit 2f6dd92c1ef5a202a3d13ff16254d2a3d7b03c02 [browse]
Author: Jay Conrod
Date: 2020-02-28 16:31:19 -05:00

[release-branch.go1.13] cmd/go: make module zip extraction more robust

Currently, we extract module zip files to temporary directories, then
atomically rename them into place. On Windows, this can fail with
ERROR_ACCESS_DENIED if another process (antivirus) has files open
before the rename. In CL 220978, we repeated the rename operation in a
loop over 500 ms, but this didn't solve the problem for everyone.

A better solution will extract module zip files to their permanent
locations in the cache and will keep a ".partial" marker file,
indicating when a module hasn't been fully extracted (CL 221157).
This approach is not safe if current versions of Go access the module
cache concurrently, since the module directory is detected with a
single os.Stat.

In the interim, this CL makes two changes:

1. Flaky file system operations are repeated over 2000 ms to reduce
the chance of this error occurring.
2. cmd/go will now check for .partial files created by future
versions. If a .partial file is found, it will lock the lock file,
then remove the .partial file and directory if needed.

After some time has passed and Go versions lacking this CL are no
longer supported, we can start extracting module zip files in place.

Updates #37802

Change-Id: I467ee11aa59a90b63cf0e3e761c4fec89d57d3b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/221820
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
(cherry picked from commit 093049b3709eda7537ece92a2991918cf53782d6)
Reviewed-on: https://go-review.googlesource.com/c/go/+/223146