Otherwise, if a signal occurs just after we allocated the M,
we can deadlock if the signal handler needs to allocate an M
itself.
For #42207Fixes#42636
Change-Id: I76f44547f419e8b1c14cbf49bf602c6e645d8c14
Reviewed-on: https://go-review.googlesource.com/c/go/+/265759
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
(cherry picked from commit 368c401164)
Reviewed-on: https://go-review.googlesource.com/c/go/+/271847
The previous s value could cause a crash
for certain inputs.
Will check in tests and documentation improvements later.
Thanks to the Go Ethereum team and the OSS-Fuzz project for reporting this.
Thanks to Rémy Oudompheng and Robert Griesemer for their help
developing and validating the fix.
Fixes CVE-2020-28362
Change-Id: Ibbf455c4436bcdb07c84a34fa6551fb3422356d3
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/899974
Reviewed-by: Roland Shoemaker <bracewell@google.com>
Reviewed-by: Filippo Valsorda <valsorda@google.com>
(cherry picked from commit 28015462c2a83239543dc2bef651e9a5f234b633)
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/901065
Restrict -D and -U to ASCII C identifiers, but do permit trailing digits.
When using -Wp, prohibit commas in -D values.
Thanks to Imre Rad (https://www.linkedin.com/in/imre-rad-2358749b) for reporting this.
Fixes CVE-2020-28367
Change-Id: Ibfc4dfdd6e6c258e131448e7682610c44eee9492
Reviewed-on: https://go-review.googlesource.com/c/go/+/267277
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/899924
Reviewed-by: Filippo Valsorda <valsorda@google.com>
A hand-edited object file can have a symbol name that uses newline and
other normally invalid characters. The cgo tool will generate Go files
containing symbol names, unquoted. That can permit those symbol names
to inject Go code into a cgo-generated file. If that Go code uses the
//go:cgo_ldflag pragma, it can cause the C linker to run arbitrary
code when building a package. If you build an imported package we
permit arbitrary code at run time, but we don't want to permit it at
package build time. This CL prevents this in two ways.
In cgo, reject invalid symbols that contain non-printable or space
characters, or that contain anything that looks like a Go comment.
In the go tool, double check all //go:cgo_ldflag directives in
generated code, to make sure they follow the existing LDFLAG restrictions.
Thanks to Chris Brown and Tempus Ex for reporting this.
Fixes CVE-2020-28366
Change-Id: Ia1ad8f3791ea79612690fa7d26ac451d0f6df7c1
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/895832
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
(cherry picked from commit 6bc814dd2bbfeaafa41d314dd4cc591b575dfbf6)
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/901056
Reviewed-by: Filippo Valsorda <valsorda@google.com>
Reviewed-by: Roland Shoemaker <bracewell@google.com>
For #42334Fixes#42369
Change-Id: Ife51df4e7d2539a04393abfdec45e3f902975fca
Reviewed-on: https://go-review.googlesource.com/c/go/+/266940
Trust: Tobias Klauser <tobias.klauser@gmail.com>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
(cherry picked from commit 633f9e2060)
Reviewed-on: https://go-review.googlesource.com/c/go/+/267917
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Change-Id: Ibcd61e2c7ef7cc6f8509dadea6c3952c5dd7016e
Reviewed-on: https://go-review.googlesource.com/c/go/+/267879
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The extend information of a time zone file with last transition < now
could result in a wrong cached zone because it used the zone of the
last transition.
This could lead to wrong zones in systems with slim zoneinfo.
For #42216Fixes#42138
Change-Id: I7c57c35b5cfa58482ac7925b5d86618c52f5444d
Reviewed-on: https://go-review.googlesource.com/c/go/+/264939
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
(cherry picked from commit 70e022e4a8)
Reviewed-on: https://go-review.googlesource.com/c/go/+/266299
Trust: Ian Lance Taylor <iant@golang.org>
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Backport of part of https://golang.org/cl/261877 to support the slim
tzdata format. As of tzdata 2020b, the default is to use the slim format.
We need to support that format so that Go installations continue to
work when tzdata is updated.
Relevant part of the CL description:
The reason for the failed tests was that when caching location data, the
extended time format past the end of zone transitions was not
considered. The respective change was introduced in (*Location).lookup
by CL 215539.
For #42138
Change-Id: I37f52a0917b2c6e3957e6b4612c8ef104c736e65
Reviewed-on: https://go-review.googlesource.com/c/go/+/264301
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
The fastest compression mode can pick up a false match for every 2GB
of input data resulting in incorrectly decompressed data.
Since matches are allowed to be up to and including at maxMatchOffset
we must offset the buffer by an additional element to prevent the first
4 bytes to match after an out-of-reach value after shiftOffsets has
been called.
We offset by `maxMatchOffset + 1` so offset 0 in the table will now
fail the `if offset > maxMatchOffset` in all cases.
Updates #41420.
Fixes#41463.
Change-Id: If1fbe01728e132b8a207e3f3f439edd832dcc710
GitHub-Last-Rev: 50fabab0da
GitHub-Pull-Request: golang/go#41477
Reviewed-on: https://go-review.googlesource.com/c/go/+/255879
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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(cherry picked from commit ab541a0560)
Reviewed-on: https://go-review.googlesource.com/c/go/+/266177
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Follow-up for CL 265819.
Given the -pre tag added recently, a new stable version is likely
tagged soon. This would break TestCodeRepoVersions on the longtest
builders again. Since the other test cases in codeRepoVersionsTests
already provide enough coverage, drop gopkg.in/russross/blackfriday.v2
to avoid breaking TestCodeRepoVersions once the release happens.
Updates #28856
Change-Id: If86a637b5e47f59faf9048fc1cbbae6e8f1dcc53
Reviewed-on: https://go-review.googlesource.com/c/go/+/265917
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Reviewed-by: Jay Conrod <jayconrod@google.com>
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(cherry picked from commit 421d4e72de)
Reviewed-on: https://go-review.googlesource.com/c/go/+/266178
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Trust: Jay Conrod <jayconrod@google.com>
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Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
storeType splits compound stores up into a scalar parts and a pointer parts.
The scalar part happens unconditionally, and the pointer part happens
under the guard of a write barrier check.
Types which are declared as pointers, but are represented as scalars because
they might have "bad" values, were not handled correctly here. They ended
up not getting stored in either set.
Fixes#42151
Change-Id: I46f6600075c0c370e640b807066247237f93c7ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/264300
Trust: Keith Randall <khr@golang.org>
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(cherry picked from commit 933721b8c7)
Reviewed-on: https://go-review.googlesource.com/c/go/+/265719
Run-TryBot: Keith Randall <khr@golang.org>
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pointers to go:notinheap types should be treated as scalars. That
means they shouldn't be stored directly in interfaces, or directly
in reflect.Value.ptr.
Also be sure to use uintpr to compare such pointers in reflect.DeepEqual.
Fixes#42169
Change-Id: I53735f6d434e9c3108d4940bd1bae14c61ef2a74
Reviewed-on: https://go-review.googlesource.com/c/go/+/264480
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
(cherry picked from commit 009d714098)
Reviewed-on: https://go-review.googlesource.com/c/go/+/265720
Run-TryBot: Keith Randall <khr@golang.org>
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During Go 1.15 development, a fix was added to the toolchain for issue
information. The 1.15 line tables were slightly malformed in the way
that they used the DWARF "end sequence" operator, resulting in
incorrect line table info for the final instruction in the final
function of a compilation unit.
This problem was fixed in https://golang.org/cl/235739, which made it
into Go 1.15. It now appears that while the fix works OK for linux, in
certain cases it causes issues with the Darwin linker (the "address
not in any section" ld64 error reported in issue #40974).
During Go 1.16 development, the fix in https://golang.org/cl/235739
was revised so as to fix another related problem (described in issue #39757);
the newer fix does not trigger the problem in the Darwin linker however.
This CL back-ports the changes in https://golang.org/cl/239286 to the
1.15 release branch, so as to fix the Darwin linker error.
Updates #38192.
Updates #39757.
Fixes#40974.
Change-Id: I9350fec4503cd3a76b97aaea0d8aed1511662e29
Reviewed-on: https://go-review.googlesource.com/c/go/+/258422
Run-TryBot: Than McIntosh <thanm@google.com>
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Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Than McIntosh <thanm@google.com>
On current macOS versions a program that receives a signal during an
execve can fail with a SIGILL signal. This appears to be a macOS
kernel bug. It has been reported to Apple.
This CL partially works around the problem by using execLock to not
send preemption signals during execve. Of course some other stray
signal could occur, but at least we can avoid exacerbating the problem.
We can't simply disable signals, as that would mean that the exec'ed
process would start with all signals blocked, which it likely does not
expect.
For #41702Fixes#41704
Change-Id: I91b0add967b315671ddcf73269c4d30136e579b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/262438
Trust: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
(cherry picked from commit 64fb6ae95f)
Reviewed-on: https://go-review.googlesource.com/c/go/+/262717
Change-Id: I8a45870039d0d3f210d883c464a7fed2abd9e28b
Reviewed-on: https://go-review.googlesource.com/c/go/+/262337
Run-TryBot: Alexander Rakoczy <alex@golang.org>
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The 32-bit left shift constant folding rule should keep its result
properly sign extended.
Fixes#41720Fixes#41711
Change-Id: I0fc74444d444274e911952e1725dab0b7737a846
Reviewed-on: https://go-review.googlesource.com/c/go/+/258817
Trust: Keith Randall <khr@golang.org>
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Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
The signature of call16 is currently missing the "typ" parameter. This
CL fixes this. This wasn't caught by vet because call16 is defined by
macro expansion (see #17544), and we didn't notice the mismatch with
the other call* functions because call16 is defined only on 32-bit
architectures and lives alone in stubs32.go.
Unfortunately, this means its GC signature is also wrong: the "arg"
parameter is treated as a scalar rather than a pointer, so GC won't
trace it and stack copying won't adjust it. This turns out to matter
in exactly one case right now: on 32-bit architectures (which are the
only architectures where call16 is defined), a stack-allocated defer
of a function with a 16-byte or smaller argument frame including a
non-empty result area can corrupt memory if the deferred function
grows the stack and is invoked during a panic. Whew. All other current
uses of reflectcall pass a heap-allocated "arg" frame (which happens
to be reachable from other stack roots, so tracing isn't a problem).
Curiously, in 2016, the signatures of all call* functions were wrong
in exactly this way. CL 31654 fixed all of them in stubs.go, but
missed the one in stubs32.go.
Updates #41795.
Fixes#41797.
Change-Id: I31e3c0df201f79ee5707eeb8dc4ff0d13fc10ada
Reviewed-on: https://go-review.googlesource.com/c/go/+/259338
Trust: Austin Clements <austin@google.com>
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Reviewed-on: https://go-review.googlesource.com/c/go/+/259598
In the rare case when a cgo type makes it into an object file, we need
the go:notinheap annotation to go with it.
Fixes#41432.
Change-Id: Ie2ef241ee49661792e0d8c8c46c51b2fe5c6fa7c
Reviewed-on: https://go-review.googlesource.com/c/go/+/259300
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
//go:notinheap
type T int
type U T
We already correctly propagate the notinheap-ness of T to U. But we
have an assertion in the typechecker that if there's no explicit
//go:notinheap associated with U, then report an error. Get rid of
that error so that implicit propagation is allowed.
Adjust the tests so that we make sure that uses of types like U
do correctly report an error when U is used in a context that might
cause a Go heap allocation.
Update #41432
Change-Id: I1692bc7cceff21ebb3f557f3748812a40887118d
Reviewed-on: https://go-review.googlesource.com/c/go/+/255637
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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(cherry picked from commit 22053790fa)
Reviewed-on: https://go-review.googlesource.com/c/go/+/255697
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
They can't reasonably be allocated on the heap. Not a huge deal, but
it has an interesting and useful side effect.
After CL 249917, the compiler and runtime treat pointers to
go:notinheap types as uintptrs instead of real pointers (no write
barrier, not processed during stack scanning, ...). That feature is
exactly what we want for cgo to fix#40954. All the cases we have of
pointers declared in C, but which might actually be filled with
non-pointer data, are of this form (JNI's jobject heirarch, Darwin's
CFType heirarchy, ...).
Fixes#40954
Change-Id: I44a3b9bc2513d4287107e39d0cbbd0efd46a3aae
Reviewed-on: https://go-review.googlesource.com/c/go/+/250940
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The alias doesn't need to be marked go:notinheap. It gets its
notinheap-ness from the target type.
Without this change, the type alias test in the notinheap.go file
generates these two errors:
notinheap.go:62: misplaced compiler directive
notinheap.go:63: type nih must be go:notinheap
The first is a result of go:notinheap pragmas not applying
to type alias declarations.
The second is the result of then trying to match the notinheap-ness
of the alias and the target type.
Add a few more go:notinheap tests while we are here.
Update #40954
Change-Id: I067ec47698df6e9e593e080d67796fd05a1d480f
Reviewed-on: https://go-review.googlesource.com/c/go/+/250939
Run-TryBot: Keith Randall <khr@golang.org>
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Trust: Keith Randall <khr@golang.org>
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Trust: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Austin Clements <austin@google.com>
Right now we just prevent such types from being on the heap. This CL
makes it so they cannot appear on the stack either. The distinction
between heap and stack is pretty vague at the language level (e.g. it
is affected by -N), and we don't need the flexibility anyway.
Once go:notinheap types cannot be in either place, we don't need to
consider pointers to such types to be pointers, at least according to
the garbage collector and stack copying. (This is the big win of this
CL, in my opinion.)
The distinction between HasPointers and HasHeapPointer no longer
exists. There is only HasPointers.
This CL is cleanup before possible use of go:notinheap to fix#40954.
Update #13386
Change-Id: Ibd895aadf001c0385078a6d4809c3f374991231a
Reviewed-on: https://go-review.googlesource.com/c/go/+/255320
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
More ergonomic that way. Also change Haspointers to HasPointers
while we are here.
Change-Id: I45bedc294c1a8c2bd01dc14bd04615ae77555375
Reviewed-on: https://go-review.googlesource.com/c/go/+/249959
Run-TryBot: Keith Randall <khr@golang.org>
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Trust: Keith Randall <khr@golang.org>
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The second argument of StorepNoWB must be forced to escape.
The current Go code does not explicitly enforce that property.
By implementing in assembly, and not using go:noescape, we
force the issue.
Test is in CL 249761. Issue #40975.
This CL is needed for CL 249917, which changes how go:notinheap
works and breaks the previous StorepNoWB wasm code.
I checked for other possible errors like this. This is the only
go:notinheap that isn't in the runtime itself.
Included test from CL 249761.
Update #41432
Change-Id: I43400a806662655727c4a3baa8902b63bdc9fa57
Reviewed-on: https://go-review.googlesource.com/c/go/+/249962
Run-TryBot: Keith Randall <khr@golang.org>
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(cherry picked from commit c0602603b2)
Reviewed-on: https://go-review.googlesource.com/c/go/+/260878
Trust: Keith Randall <khr@golang.org>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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This brings over the architectures that the gofrontend knows about.
This permits using the main cgo tool for those architectures,
as cgo can be used with -godefs without gc support.
This will help add golang.org/x/sys/unix support for other architectures.
For #37443Fixes#41871
Change-Id: I63632b9c5139e71b9ccab8edcc7acdb464229b74
Reviewed-on: https://go-review.googlesource.com/c/go/+/260657
Trust: Ian Lance Taylor <iant@golang.org>
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(cherry picked from commit 5d1378143b)
Reviewed-on: https://go-review.googlesource.com/c/go/+/260702
The IndexString implementation in the bytealg package requires that
the string passed into it be in the range '2 <= len(s) <= MaxLen'
where MaxLen may be any value (including 0).
CL 156998 added calls to bytealg.IndexString where MaxLen was not
first checked. This led to an illegal instruction on s390x with
the vector facility disabled.
This CL guards the calls to bytealg.IndexString with a MaxLen check.
If the check fails then the code now falls back to the pre CL 156998
implementation (a loop over the runes in the string).
Since the MaxLen check is now in place the generic implementation is
no longer called so I have returned it to its original unimplemented
state.
In future we may want to drop MaxLen to prevent this kind of
confusion.
Fixes#41595.
Change-Id: I81d88cf8c5ae143a8f5f460d18f8269cb6c0f28c
Reviewed-on: https://go-review.googlesource.com/c/go/+/256921
Trust: Michael Munday <mike.munday@ibm.com>
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In https://golang.org/cl/221397 we made commands like "go version -v"
error, since both of the command's flags only make sense when arguments
follow them. Without arguments, the command only reports Go's own
version, and the flags are most likely a mistake.
However, the script below is entirely reasonable:
export GOFLAGS=-v # make all Go commands verbose
go version
go build
After the previous CL, "go version" would error. Instead, only error if
the flag was passed explicitly, and not via GOFLAGS.
The patch does mean that we won't error on "GOFLAGS=-v go version -v",
but that very unlikely false negative is okay. The error is only meant
to help the user not misuse the flags, anyway - it's not a critical
error of any sort.
To reuse inGOFLAGS, we move it to the base package and export it there,
since it's where the rest of the GOFLAGS funcs are.
Fixes#41464.
Change-Id: I74003dd25d94bacf9ac507b5cad778fd65233321
Reviewed-on: https://go-review.googlesource.com/c/go/+/254157
Trust: Daniel Martí <mvdan@mvdan.cc>
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(cherry picked from commit de0957dc08)
Reviewed-on: https://go-review.googlesource.com/c/go/+/255498
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Currently activeStackChans is set before a goroutine blocks on a channel
operation in an unlockf passed to gopark. The trouble is that the
unlockf is called *after* the G's status is changed, and the G's status
is what is used by a concurrent mark worker (calling suspendG) to
determine that a G has successfully been suspended. In this window
between the status change and unlockf, the mark worker could try to
shrink the G's stack, and in particular observe that activeStackChans is
false. This observation will cause the mark worker to *not* synchronize
with concurrent channel operations when it should, and so updating
pointers in the sudog for the blocked goroutine (which may point to the
goroutine's stack) races with channel operations which may also
manipulate the pointer (read it, dereference it, update it, etc.).
Fix the problem by adding a new atomically-updated flag to the g struct
called parkingOnChan, which is non-zero in the race window above. Then,
in isShrinkStackSafe, check if parkingOnChan is zero. The race is
resolved like so:
* Blocking G sets parkingOnChan, then changes status in gopark.
* Mark worker successfully suspends blocking G.
* If the mark worker observes parkingOnChan is non-zero when checking
isShrinkStackSafe, then it's not safe to shrink (we're in the race
window).
* If the mark worker observes parkingOnChan as zero, then because
the mark worker observed the G status change, it can be sure that
gopark's unlockf completed, and gp.activeStackChans will be correct.
The risk of this change is low, since although it reduces the number of
places that stack shrinking is allowed, the window here is incredibly
small. Essentially, every place that it might crash now is replaced with
no shrink.
This change adds a test, but the race window is so small that it's hard
to trigger without a well-placed sleep in park_m. Also, this change
fixes stackGrowRecursive in proc_test.go to actually allocate a 128-byte
stack frame. It turns out the compiler was destructuring the "pad" field
and only allocating one uint64 on the stack.
For #40641.
Fixes#40643.
Change-Id: I7dfbe7d460f6972b8956116b137bc13bc24464e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/247050
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
(cherry picked from commit eb3c6a93c3)
Reviewed-on: https://go-review.googlesource.com/c/go/+/256300
Reviewed-by: Austin Clements <austin@google.com>
Taking the live variable set from the last return point is problematic.
See #40629 for details, but there may not be a return point, or it may
be before the final defer.
Additionally, keeping track of the last call as a *Value doesn't quite
work. If it is dead-code eliminated, the storage for the Value is reused
for some other random instruction. Its live variable information,
if it is available at all, is wrong.
Instead, just mark all the open-defer argument slots as live
throughout the function. (They are already zero-initialized.)
Fixes#40742
Change-Id: Ie456c7db3082d0de57eaa5234a0f32525a1cce13
Reviewed-on: https://go-review.googlesource.com/c/go/+/247522
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
(cherry picked from commit 32a84c99e1)
Reviewed-on: https://go-review.googlesource.com/c/go/+/248621
Trust: Dmitri Shuralyov <dmitshur@golang.org>
While debugging #40771, I realized that the chatty printer should only
ever print to a single io.Writer (normally os.Stdout). The other
Writer implementations in the chain write to local buffers, but if we
wrote a test's output to a local buffer, then we did *not* write it to
stdout and we should not store it as the most recently logged test.
Because the chatty printer should only ever print to one place, it
shouldn't receive an io.Writer as an argument — rather, it shouldn't
be used at all for destinations other than the main output stream.
On the other hand, when we flush the output buffer to stdout in the
top-level flushToParent call, it is important that we not allow some
other test's output to intrude between the test summary header and the
remainder of the test's output. cmd/test2json doesn't know how to
parse such an intrusion, and it's confusing to humans too.
No test because I couldn't reproduce the user-reported error without
modifying the testing package. (This behavior seems to be very
sensitive to output size and/or goroutine scheduling.)
Fixes#40881
Updates #40771
Updates #38458
Change-Id: Ic19bf1d535672b096ba1c8583a3b74aab6d6d766
Reviewed-on: https://go-review.googlesource.com/c/go/+/249026
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
(cherry picked from commit 51c0bdc6d1)
Reviewed-on: https://go-review.googlesource.com/c/go/+/252637
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Bryan C. Mills <bcmills@google.com>
The 387 port needs to load a floating-point control word from a
global location to implement float32 arithmetic.
When compiling with -pie, loading that control word clobbers an
integer register. If that register had something important in it, boom.
Fix by using LEAL to materialize the address of the global location
first. LEAL with -pie works because the destination register is
used as the scratch register.
387 support is about to go away (#40255), so this will need to be
backported to have any effect.
No test. I have one, but it requires building with -pie, which
requires cgo. Our testing infrastructure doesn't make that easy.
Not worth it for a port which is about to vanish.
Fixes#41620
Change-Id: I140f9fc8fdce4e74a52c2c046e2bd30ae476d295
Reviewed-on: https://go-review.googlesource.com/c/go/+/257277
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Keith Randall <khr@golang.org>
(cherry picked from commit ea106cc07a)
Reviewed-on: https://go-review.googlesource.com/c/go/+/257207
The 1.15 compiler is not quite smart enough to see that the byte slice
passed to ignoringEINTR does not escape. This ripples back up to user
code which would see a byte slice passed to os.(*File).Write escape,
which did not happen in 1.14.
Rather than backport some moderately complex compiler fixes, rewrite
the code slightly so that the 1.15 compiler is able to see that the
slice does not escape.
This is not a backport from tip, where the code is already different.
The test for this will be on tip, where we will most likely change the
compiler to understand this kind of code.
Fixes#41543
For #41474
Change-Id: I6c78164229fea7794e7edba512bfd7034a0b91c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/256418
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Both ReadMemStatsSlow and CheckScavengedBits iterate over the page
allocator's chunks but don't actually check if they exist. During the
development process the chunks index became sparse, so now this was a
possibility. If the runtime tests' heap is sparse we might end up
segfaulting in either one of these functions, though this will generally
be very rare.
The pattern here to return nil for a nonexistent chunk is also useful
elsewhere, so this change introduces tryChunkOf which won't throw, but
might return nil. It also updates the documentation of chunkOf.
For #41296.
Fixes#41317.
Change-Id: Id5ae0ca3234480de1724fdf2e3677eeedcf76fa0
Reviewed-on: https://go-review.googlesource.com/c/go/+/253777
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
(cherry picked from commit 34835df048)
Reviewed-on: https://go-review.googlesource.com/c/go/+/253917
The optimization that replaces inline markers with pre-existing
instructions assumes that 'Prog' values produced by the compiler are
still reachable after the assembler has run. This was not true on
s390x where the assembler was removing NOP instructions from the
linked list of 'Prog' values. This led to broken inlining data
which in turn caused an infinite loop in the runtime traceback code.
Fix this by stopping the s390x assembler backend removing NOP
values. It does not make any difference to the output of the
assembler because NOP instructions are 0 bytes long anyway.
Note: compiler check omitted from backport to reduce risk of change.
Fixes#40693.
Change-Id: I4eb570de13165cde342d5fb2ee3218945ddf4b52
Reviewed-on: https://go-review.googlesource.com/c/go/+/248478
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
When external linking, for large binaries, the external linker
may insert a trampoline for the write barrier call, which looks
0000000005a98cc8 <__long_branch_runtime.gcWriteBarrier>:
5a98cc8: 86 01 82 3d addis r12,r2,390
5a98ccc: d8 bd 8c e9 ld r12,-16936(r12)
5a98cd0: a6 03 89 7d mtctr r12
5a98cd4: 20 04 80 4e bctr
It clobbers R12 (and CTR, which is never live across a call).
As at compile time we don't know whether the binary is big and
what link mode will be used, I think we need to mark R12 as
clobbered for write barrier call. For extra safety (future-proof)
we mark caller-saved register that cannot be used for function
arguments, which includes R11, as potentially clobbered as well.
Updates #40851.
Fixes#40868.
Change-Id: Iedd901c5072f1127cc59b0a48cfeb4aaec81b519
Reviewed-on: https://go-review.googlesource.com/c/go/+/248917
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
(cherry picked from commit b58d297416)
Reviewed-on: https://go-review.googlesource.com/c/go/+/249019
This has already been done for s390x, ppc64. This CL is for
all the other architectures.
Fixes#40798
Change-Id: Idd1816e057df63022d47e99fa06617811d8c8489
Reviewed-on: https://go-review.googlesource.com/c/go/+/248684
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
(cherry picked from commit 46ca7b5ee2)
Reviewed-on: https://go-review.googlesource.com/c/go/+/249444
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Previously, the assembler removed NOPs from the Prog list in
obj9.go. NOPs shouldn't be removed if they were added as
an inline mark, as described in the issue below.
Fixes#40767
Once the NOPs were left in the Prog list, some instructions
were flagged as invalid because they had an operand which was
not represented in optab. In order to preserve the previous
assembler behavior, entries were added to optab for those
operand cases. They were not flagged as errors before because
the NOP instructions were removed before the code to check the
valid opcode/operand combinations.
Change-Id: Iae5145f94459027cf458e914d7c5d6089807ccf8
Reviewed-on: https://go-review.googlesource.com/c/go/+/247842
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Paul Murphy <murp@ibm.com>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Reviewed-by: Keith Randall <khr@golang.org>
(cherry picked from commit 7d7bd5abc7)
Reviewed-on: https://go-review.googlesource.com/c/go/+/248381
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
A test introduced in the security release is flaky due to a pre-existing
issue that does not qualify for backport itself.
Updates #41167Fixes#41193
Change-Id: Ie6014e0796c1baee7b077881b5a799f9947fc9c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/252717
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
If we are parsing a test output, and the test does not end in the
usual PASS or FAIL line (say, because it panicked), then we need the
exit status of the test binary in order to determine whether the test
passed or failed. If we don't have that status available, we shouldn't
guess arbitrarily — instead, we should omit the final "pass" or "fail"
action entirely.
(In practice, we nearly always DO have the final status, such as when
running 'go test' or 'go tool test2json some.exe'.)
Updates #40132Fixes#40805
Change-Id: Iae482577361a6033395fe4a05d746b980e18c3de
Reviewed-on: https://go-review.googlesource.com/c/go/+/248624
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
(cherry picked from commit 1b86bdbdc3)
Reviewed-on: https://go-review.googlesource.com/c/go/+/248725
