In the accessor functions ld*_he_p() and st*_he_p() we use memcpy()
to perform a load or store to a pointer which might not be aligned
for the size of the type. We rely on the compiler to optimize this
memcpy() into an efficient load or store instruction where possible.
This is required for good performance, but at the moment it is also
required for correct operation, because some users of these functions
require that the access is atomic if the pointer is aligned, which
will only be the case if the compiler has optimized out the memcpy().
(The particular example where we discovered this is the virtio
vring_avail_idx() which calls virtio_lduw_phys_cached() which
eventually ends up calling lduw_he_p().)
Unfortunately some compile environments, such as the fortify-source
setup used in Alpine Linux, define memcpy() to a wrapper function
in a way that inhibits this compiler optimization.
The correct long-term fix here is to add a set of functions for
doing atomic accesses into AddressSpaces (and to other relevant
families of accessor functions like the virtio_*_phys_cached()
ones), and make sure that callsites which want atomic behaviour
use the correct functions.
In the meantime, switch to using __builtin_memcpy() in the
bswap.h accessor functions. This will make us robust against things
like this fortify library in the short term. In the longer term
it will mean that we don't end up with these functions being really
badly-performing even if the semantics of the out-of-line memcpy()
are correct.
This ports over the RISC-V architecture from Qemu. This is currently a
very barebones transition. No code hooking or any fancy stuff.
Currently, you can feed it instructions and query the CPU state itself.
This also allows choosing whether or not RISC-V 32-bit or RISC-V 64-bit
is desirable through Unicorn's interface as well.
Extremely basic examples of executing a single instruction have been
added to the samples directory to help demonstrate how to use the basic
functionality.
Handling it just like float128_to_uint32_round_to_zero, that hopefully
is free of bugs :)
Documentation basically copied from float128_to_uint64
Backports commit e45de9922e43c1ce4f4739b62142314a13029d5c from qemu
Needed on s390x, to test for the data class of a number. So it will
gain soon a user.
A number is considered normal if the exponent is neither 0 nor all 1's.
That can be checked by adding 1 to the exponent, and comparing against
>= 2 after dropping an eventual overflow into the sign bit.
While at it, convert the other floatXX_is_normal functions to use a
similar, less error prone calculation, as suggested by Richard H.
Backports commit 47393181604d507f4fe2a15a65b1eede0f974d6a from qemu
Especially when dealing with out-of-line gvec helpers, it is often
helpful to specify some vector pointers as constant. E.g. when
we have two inputs and one output, marking the two inputs as consts
pointers helps to avoid bugs.
Const pointers can be specified via "cptr", however behave in TCG just
like ordinary pointers. We can specify helpers like:
DEF_HELPER_FLAGS_4(gvec_vbperm, TCG_CALL_NO_RWG, void, ptr, cptr, cptr, i32)
void HELPER(gvec_vbperm)(void *v1, const void *v2, const void *v3,
uint32_t desc)
And make sure that here, only v1 will be written (as long as const is
not casted away, of course).
Backports commit 8c6edfdd90522caa4fc429144d393aba5b99f584 from qemu
There are a whole bunch more registers in the CPUID space which are
currently not used but are exposed as RAZ. To avoid too much
duplication we expand ARMCPRegUserSpaceInfo to understand glob
patterns so we only need one entry to tweak whole ranges of registers.
Backports commit d040242effe47850060d2ef1c461ff637d88a84d from qemu
Without this patch, gcc might up the Input/Output registers and
cause unpredictable error.
Fixes: 1ec182c33379 ("target/arm: Convert to HAVE_CMPXCHG128")
Backports commit 7400d6938c6d455c4eba2b80c06d60c8fa5c5ba3 from qemu
These bits can be used to cache target-specific data in cputlb
read from the page tables.
Backports commit d3765835ed02f91f0c6cbb452874209a6af4a730 from qemu
The commit 7197fb4058bcb68986bae2bb2c04d6370f3e7218 ("util/mmap-alloc:
fix hugetlb support on ppc64") fixed Huge TLB mappings on ppc64.
However, we still need to consider the underlying huge page size
during munmap() because it requires that both address and length be a
multiple of the underlying huge page size for Huge TLB mappings.
Quote from "Huge page (Huge TLB) mappings" paragraph under NOTES
section of the munmap(2) manual:
"For munmap(), addr and length must both be a multiple of the
underlying huge page size."
On ppc64, the munmap() in qemu_ram_munmap() does not work for Huge TLB
mappings because the mapped segment can be aligned with the underlying
huge page size, not aligned with the native system page size, as
returned by getpagesize().
This has the side effect of not releasing huge pages back to the pool
after a hugetlbfs file-backed memory device is hot-unplugged.
This patch fixes the situation in qemu_ram_mmap() and
qemu_ram_munmap() by considering the underlying page size on ppc64.
After this patch, memory hot-unplug releases huge pages back to the
pool.
Fixes: 7197fb4058bcb68986bae2bb2c04d6370f3e7218
Backports commit 53adb9d43e1abba187387a51f238e878e934c647 from qemu
Until now, the set_pc logic was unclear, which raised questions about
whether it should be used directly, applying a value to PC or adding
additional checks, for example, set the Thumb bit in Arm cpu. Let's set
the set_pc logic for “Configure the PC, as was done in the ELF file”
and implement synchronize_with_tb hook for preserving PC to cpu_tb_exec.
Backports commit 42f6ed919325413392bea247a1e6f135deb469cd from qemu
Some files claim that the code is licensed under the GPL, but then
suddenly suggest that the user should have a look at the LGPL.
That's of course non-sense, replace it with the correct GPL wording
instead.
Backports commit e361a772ffcd33675ffdd4637eea98a460dfed1b from qemu
For TCG we want to distinguish which cluster a CPU is in, and
we need to do it quickly. Cache the cluster index in the CPUState
struct, by having the cluster object set cpu->cluster_index for
each CPU child when it is realized.
This means that board/SoC code must add all CPUs to the cluster
before realizing the cluster object. Regrettably QOM provides no
way to prevent adding children to a realized object and no way for
the parent to be notified when a new child is added to it, so
we don't have any way to enforce/assert this constraint; all
we can do is document it in a comment. We can at least put in a
check that the cluster contains at least one CPU, which should
catch the typical cases of "realized cluster too early" or
"forgot to parent the CPUs into it".
The restriction on how many clusters can exist in the system
is imposed by TCG code which will be added in a subsequent commit,
but the check to enforce it in cluster.c fits better in this one.
Backports relevant parts of commit 7ea7b9ad532e59c3efbcabff0e3484f4df06104c from qemu
GCC 8 introduced the -Wstringop-truncation checker to detect truncation by
the strncat and strncpy functions (closely related to -Wstringop-overflow,
which detect buffer overflow by string-modifying functions declared in
<string.h>).
In tandem of -Wstringop-truncation, the "nonstring" attribute was added:
The nonstring variable attribute specifies that an object or member
declaration with type array of char, signed char, or unsigned char,
or pointer to such a type is intended to store character arrays that
do not necessarily contain a terminating NUL. This is useful in detecting
uses of such arrays or pointers with functions that expect NUL-terminated
strings, and to avoid warnings when such an array or pointer is used as
an argument to a bounded string manipulation function such as strncpy.
From the GCC manual: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-nonstring-variable-attribute
Add the QEMU_NONSTRING macro which checks if the compiler supports this
attribute.
Backports commit 1daff2f8193496b0e5e0ab56dc48c570c81f804e from qemu
Both qemu & qga build with Vista API by default already, by defining
_WIN32_WINNT 0x0600. Set it globally in osdep.h instead.
This replaces WINVER by _WIN32_WINNT in osdep.h. WINVER doesn't seem
to be really useful these days.
(see also https://blogs.msdn.microsoft.com/oldnewthing/20070411-00/?p=27283)
Backports commit 56cdca1d7a6a9c8ce28287b8c986ac9ea87ba603 from qemu
This removes some clutter in compilation logging, and allows some
easier tweaking per compilation unit/CFLAGS overriding.
Note that we can't move those define in os-win32.h, since they must be
set before the first system headers are included.
Backports commit 007e722c349839f430f10639ba8c94fe43acfe50 from qemu
ATOMIC_REG_SIZE is currently defined as the default sizeof(void *) for
all MIPS host builds, including those using the n32 ABI. n32 is the
MIPS64 ILP32 ABI and as such tcg/mips/tcg-target.h defines
TCG_TARGET_REG_BITS as 64 for n32 builds. If we attempt to build QEMU
for an n32 host with support for a 64b target architecture then
TCG_OVERSIZED_GUEST is 0 and accel/tcg/cputlb.c attempts to use
atomic_* functions. This fails because ATOMIC_REG_SIZE is 4, causing
the calls to QEMU_BUILD_BUG_ON(sizeof(*ptr) > ATOMIC_REG_SIZE) in the
various atomic_* functions to generate errors.
Fix this by defining ATOMIC_REG_SIZE as 8 for all MIPS64 builds, which
will cover both n32 (ILP32) & n64 (LP64) ABIs in much the same was as
we already do for x86_64/x32.
Backports commit c5b00c1684f3317e887c7401b58dde54c2b05354 from qemu
Change the order in which we extract a/b and c/d to
match the output of the upstream xxhash32.
Tested with:
https://github.com/cota/xxhash/tree/qemu
Backports commit b7c2cd08a6f68010ad27c9c0bf2fde02fb743a0e from qemu
The input visitor has some problems right now, especially
- unsigned type "Range" is used to process signed ranges, resulting in
inconsistent behavior and ugly/magical code
- uint64_t are parsed like int64_t, so big uint64_t values are not
supported and error messages are misleading
- lists/ranges of int64_t are accepted although no list is parsed and
we should rather report an error
- lists/ranges are preparsed using int64_t, making it hard to
implement uint64_t values or uint64_t lists
- types that don't support lists don't bail out
- visiting beyond the end of a list is not handled properly
- we don't actually parse lists, we parse *sets*: members are sorted,
and duplicates eliminated
So let's rewrite it by getting rid of usage of the type "Range" and
properly supporting lists of int64_t and uint64_t (including ranges of
both types), fixing the above mentioned issues.
Lists of other types are not supported and will properly report an
error. Virtual walks are now supported.
Tests have to be fixed up:
- Two BUGs were hardcoded that are fixed now
- The string-input-visitor now actually returns a parsed list and not
an ordered set.
Please note that no users/callers have to be fixed up. Candidates using
visit_type_uint16List() and friends are:
- backends/hostmem.c:host_memory_backend_set_host_nodes()
-- Code can deal with duplicates/unsorted lists
- numa.c::query_memdev()
-- via object_property_get_uint16List(), the list will still be sorted
and without duplicates (via host_memory_backend_get_host_nodes())
- qapi-visit.c::visit_type_Memdev_members()
- qapi-visit.c::visit_type_NumaNodeOptions_members()
- qapi-visit.c::visit_type_RockerOfDpaGroup_members
- qapi-visit.c::visit_type_RxFilterInfo_members()
-- Not used with string-input-visitor.
Backports commit c9fba9de89db51a07689e2cba4865a1e564b8f0f from qemu
qemu_strtosz() & friends reject NaNs, but happily accept infinities.
They shouldn't. Fix that.
The fix makes use of qemu_strtod_finite(). To avoid ugly casts,
change the @end parameter of qemu_strtosz() & friends from char **
to const char **.
Also, add two test cases, testing that "inf" and "NaN" are properly
rejected. While at it, also fixup the function documentation.
Backports commit af02f4c5179675ad4e26b17ba26694a8fcde17fa from qemu
The code that used it has already been removed a while ago with commit
dc41aa7d34989b552ef ("tcg: Remove GET_TCGV_* and MAKE_TCGV_*").
Backports commit 78751ea855f89b5a352ccc332162fed3ad4c9496 from qemu
Since we require GCC version 4.8 or newer now, we can be sure that
the builtin functions are always available on GCC. And for Clang,
we can check the availablility with __has_builtin instead.
Backports commit f773b423cc61f3ca18af5337101c158a52aaae2c from qemu
Add support for MMU protection regions that are smaller than
TARGET_PAGE_SIZE. We do this by marking the TLB entry for those
pages with a flag TLB_RECHECK. This flag causes us to always
take the slow-path for accesses. In the slow path we can then
special case them to always call tlb_fill() again, so we have
the correct information for the exact address being accessed.
This change allows us to handle reading and writing from small
regions; we cannot deal with execution from the small region.
Backports commit 55df6fcf5476b44bc1b95554e686ab3e91d725c5 from qemu
Add a new flag to mark memory region that are used as non-volatile, by
NVDIMM for example. That bit is propagated down to the flat view, and
reflected in HMP info mtree with a "nv-" prefix on the memory type.
This way, guest_phys_blocks_region_add() can skip the NV memory
regions for dumps and TCG memory clear in a following patch.
Backports commit c26763f8ec70b1011098cab0da9178666d8256a5 from qemu
GCC7+ will no longer advertise support for 16-byte __atomic operations
if only cmpxchg is supported, as for x86_64. Fortunately, x86_64 still
has support for __sync_compare_and_swap_16 and we can make use of that.
AArch64 does not have, nor ever has had such support, so open-code it.
Backports commit e6cd4bb59b8154fa00da611200beef7eb4e8ec56 from qemu
Isolate the computation of an index from an address into a
helper before we change that function.
Backports commit 383beda9cf32f795616c3b93f7d6154d70372d4b from qemu
