On m68k, an fmove instruction accessing %fpcr may only move from
or to a data register or a memory operand. The constraint "g" also
permits the use of address registers, which is invalid. The correct
constraint is "dm". Beginning with GCC 15, the register allocator
picks an address register in the code which causes SIGILL during
runtime.
(cherry picked from commit 02c085d48b)
Co-authored-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Co-authored-by: Michael Karcher <github@mkarcher.dialup.fu-berlin.de>
gh-140815: Fix faulthandler for invalid/freed frame (#140921)
faulthandler now detects if a frame or a code object is invalid or
freed.
Add helper functions:
* _PyCode_SafeAddr2Line()
* _PyFrame_SafeGetCode()
* _PyFrame_SafeGetLasti()
_PyMem_IsPtrFreed() now detects pointers in [-0xff, 0xff] range
as freed.
(cherry picked from commit a84181c31b)
There were a few thread-safety issues when profiling or tracing all
threads via PyEval_SetProfileAllThreads or PyEval_SetTraceAllThreads:
* The loop over thread states could crash if a thread exits concurrently
(in both the free threading and default build)
* The modification of `c_profilefunc` and `c_tracefunc` wasn't
thread-safe on the free threading build.
(cherry picked from commit a10152f8fd)
* [3.13] gh-87135: Hang non-main threads that attempt to acquire the GIL during finalization (GH-105805)
Instead of surprise crashes and memory corruption, we now hang threads that attempt to re-enter the Python interpreter after Python runtime finalization has started. These are typically daemon threads (our long standing mis-feature) but could also be threads spawned by extension modules that then try to call into Python. This marks the `PyThread_exit_thread` public C API as deprecated as there is no plausible safe way to accomplish that on any supported platform in the face of things like C++ code with finalizers anywhere on a thread's stack. Doing this was the least bad option.
(cherry picked from commit 8cc5aa47ee)
Co-authored-by: Jeremy Maitin-Shepard <jeremy@jeremyms.com>
Co-authored-by: Gregory P. Smith <greg@krypto.org>
* state "3.13.7 and earlier"
* backport: do not add the deprecated marker
* fix Py_IsFinalizing doc ref
---------
Co-authored-by: Jeremy Maitin-Shepard <jeremy@jeremyms.com>
(cherry picked from commit 698bab5a40)
Co-authored-by: Weilin Du <108666168+LamentXU123@users.noreply.github.com>
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
The free threading build uses QSBR to delay the freeing of dictionary
keys and list arrays when the objects are accessed by multiple threads
in order to allow concurrent reads to proceed with holding the object
lock. The requests are processed in batches to reduce execution
overhead, but for large memory blocks this can lead to excess memory
usage.
Take into account the size of the memory block when deciding when to
process QSBR requests.
Also track the amount of memory being held by QSBR for mimalloc pages.
Advance the write sequence if this memory exceeds a limit. Advancing
the sequence will allow it to be freed more quickly.
Process the held QSBR items from the "eval breaker", rather than from
`_PyMem_FreeDelayed()`. This gives a higher chance that the global read
sequence has advanced enough so that items can be freed.
(cherry picked from commit 113de8545f)
Co-authored-by: Neil Schemenauer <nas-github@arctrix.com>
Co-authored-by: Sam Gross <colesbury@gmail.com>
gh-135607: remove null checking of weakref list in dealloc of extension modules and objects (#135614)
(cherry picked from commit b1056c2a44)
Co-authored-by: Xuanteng Huang <44627253+xuantengh@users.noreply.github.com>
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
gh-134875: Fix mimallc build error for the old compilers (gh-134994)
(cherry picked from commit b525e31b7f)
Co-authored-by: Donghee Na <donghee.na@python.org>
gh-129748: Update mimalloc to use atomic store for mi_block_set_nextx (GH-134238)
(cherry picked from commit 317c496223)
Co-authored-by: Donghee Na <donghee.na@python.org>
If the error handler is used, a new bytes object is created to set as
the object attribute of UnicodeDecodeError, and that bytes object then
replaces the original data. A pointer to the decoded data will became invalid
after destroying that temporary bytes object. So we need other way to return
the first invalid escape from _PyUnicode_DecodeUnicodeEscapeInternal().
_PyBytes_DecodeEscape() does not have such issue, because it does not
use the error handlers registry, but it should be changed for compatibility
with _PyUnicode_DecodeUnicodeEscapeInternal().
(cherry picked from commit 9f69a58623)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Use the standard `__ARM_ARCH` macro, which is supported by GCC and Clang.
The branching logic for of `__ARMEL__` has been removed so if the target
architecture supports v7+ instructions, a yield is emitted, otherwise a nop
is emitted. This covers both big and little endian scenarios.
(cherry picked from commit 03f6c8e239)
Signed-off-by: Vincent Fazio <vfazio@gmail.com>
Co-authored-by: Vincent Fazio <vfazio@gmail.com>
The use of PySys_GetObject() and _PySys_GetAttr(), which return a borrowed
reference, has been replaced by using one of the following functions, which
return a strong reference and distinguish a missing attribute from an error:
_PySys_GetOptionalAttr(), _PySys_GetOptionalAttrString(),
_PySys_GetRequiredAttr(), and _PySys_GetRequiredAttrString().
(cherry picked from commit 0ef4ffeefd)
We should use a relaxed atomic load in the free threading build in
`PyType_Modified()` because that's called without the type lock held.
It's not necessary to use atomics in `type_modified_unlocked()`.
We should also use `FT_ATOMIC_STORE_UINT_RELAXED()` instead of the
`UINT32` variant because `tp_version_tag` is declared as `unsigned int`.
(cherry picked from commit 57f45ee2d8)
The MemoryError freelist was not thread-safe in the free threaded build.
Use a mutex to protect accesses to the freelist. Unlike other freelists,
the MemoryError freelist is not performance sensitive.
(cherry picked from commit 51b4edb1a4)
tracemalloc_alloc(), tracemalloc_realloc(), PyTraceMalloc_Track(),
PyTraceMalloc_Untrack() and _PyTraceMalloc_TraceRef() now check
tracemalloc_config.tracing after calling TABLES_LOCK().
_PyTraceMalloc_Stop() now protects more code with TABLES_LOCK(),
especially setting tracemalloc_config.tracing to 1.
Add a test using PyTraceMalloc_Track() to test tracemalloc.stop()
race condition.
Call _PyTraceMalloc_Init() at Python startup.
Previously, `_Py_RefcntAdd` hasn't called
`_Py_INCREF_STAT_INC/_Py_INCREF_IMMORTAL_STAT_INC` which is incorrect.
Now it has been fixed.
(cherry picked from commit ab05beb8ce)
Objects may be temporarily "resurrected" in destructors when calling
finalizers or watcher callbacks. We previously undid the resurrection
by decrementing the reference count using `Py_SET_REFCNT`. This was not
thread-safe because other threads might be accessing the object
(modifying its reference count) if it was exposed by the finalizer,
watcher callback, or temporarily accessed by a racy dictionary or list
access.
This adds internal-only thread-safe functions for temporary object
resurrection during destructors.
(cherry picked from commit f4f530804b)
gh-122907: Fix Builds Without HAVE_DYNAMIC_LOADING Set (gh-122952)
As of 529a160 (gh-118204), building with HAVE_DYNAMIC_LOADING stopped working. This is a minimal fix just to get builds working again. There are actually a number of long-standing deficiencies with HAVE_DYNAMIC_LOADING builds that need to be resolved separately.
(cherry picked from commit ee1b8ce26e)
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
This approach eliminates the originally reported race. It also gets rid of the deadlock reported in gh-96071, so we can remove the workaround added then.
This is mostly a cherry-pick of 1c0a104 (AKA gh-126989). The difference is we add PyInterpreterState.threads_preallocated at the end of PyInterpreterState, instead of adding PyInterpreterState.threads.preallocated. That avoids ABI disruption.
The PyMutex implementation supports unlocking after fork because we
clear the list of waiters in parking_lot.c. This doesn't work as well
for _PyRecursiveMutex because on some systems, such as SerenityOS, the
thread id is not preserved across fork().
(cherry picked from commit 5610860840)
Co-authored-by: Sam Gross <colesbury@gmail.com>
When formatting the AST as a string, infinite values are replaced by
1e309, which evaluates to infinity. The initialization of this string
replacement was not thread-safe in the free threading build.
(cherry picked from commit 427dcf24de)
This fixes a crash when `gc.get_objects()` or `gc.get_referrers()` is
called during a GC in the free threading build.
Switch to `_PyObjectStack` to avoid corrupting the `struct worklist`
linked list maintained by the GC. Also, don't return objects that are frozen
(`gc.freeze()`) or in the process of being collected to more closely match
the behavior of the default build.
(cherry picked from commit e545ead66c)
Co-authored-by: Sam Gross <colesbury@gmail.com>
On Arm v5 it is not possible to get the thread ID via c13 register
hence the illegal instruction. The c13 register started to provide
thread ID since Arm v6K architecture variant. Other variants of
Arm v6 (T2, Z and base) don’t provide the thread ID via c13.
For the sake of simplicity we group v5 and v6 together and
consider that instructions for Arm v7 only.
(cherry picked from commit feda9aa73a)
Co-authored-by: Diego Russo <diego.russo@arm.com>
Revert the incremental GC in 3.13, since it's not clear that without further turning, the benefits outweigh the costs.
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
gh-123091: Use _Py_IsImmortalLoose() (#123511)
Use _Py_IsImmortalLoose() in bytesobject.c, typeobject.c
and ceval.c.
(cherry picked from commit f1a0d96f41)
gh-122584: Import mimalloc headers in a C++ context (GH-122587)
(cherry picked from commit 1dad23edbc)
Co-authored-by: Michael Droettboom <mdboom@gmail.com>
gh-120974: Make asyncio `swap_current_task` safe in free-threaded build (GH-122317)
* gh-120974: Make asyncio `swap_current_task` safe in free-threaded build
(cherry picked from commit b5e6fb39a2)
Co-authored-by: Sam Gross <colesbury@gmail.com>
gh-121489: Export private _PyBytes_Join() again (GH-122267)
(cherry picked from commit aef95eb107)
Co-authored-by: Marc Mueller <30130371+cdce8p@users.noreply.github.com>
