It is not necessary to munmap an area before remapping it with MAP_FIXED;
if the memory region specified by addr and len overlaps pages of any
existing mapping, then the overlapped part of the existing mapping will
be discarded.
On the other hand, if QEMU does munmap the pages, there is a small
probability that another mmap sneaks in and catches the just-freed
portion of the address space. In effect, munmap followed by
mmap(MAP_FIXED) is a use-after-free error, and Coverity flags it
as such. Fix it.
Backports commit f18c69cfc554cf9776eb3c35b7510e17541afacb from qemu
This reverts commit c3c1bb9.
It causes problems with boards that declare memory regions shorter
than the registers they contain.
Backports commit 4025446f0ac6213335c22ec43f3c3d8362ce7286 from qemu
Block size must fundamentally be a multiple of target page size.
Aligning automatically removes need to worry about the alignment
from callers.
Note: the only caller of qemu_ram_resize (acpi) already happens to have
size padded to a power of 2, but we would like to drop the padding in
ACPI core, and don't want to expose target page size knowledge to ACPI
Backports commit 129ddaf31be583fb7c97812e07e028661005ce42 from qemu
Allow "unlocked" reads of the ram_list by using an RCU-enabled QLIST.
The ramlist mutex is kept. call_rcu callbacks are run with the iothread
lock taken, but that may change in the future. Writers still take the
ramlist mutex, but they no longer need to assume that the iothread lock
is taken.
Readers of the list, instead, no longer require either the iothread
or ramlist mutex, but they need to use rcu_read_lock() and
rcu_read_unlock().
One place in arch_init.c was downgrading from write side to read side
like this:
qemu_mutex_lock_iothread()
qemu_mutex_lock_ramlist()
...
qemu_mutex_unlock_iothread()
...
qemu_mutex_unlock_ramlist()
and the equivalent idiom is:
qemu_mutex_lock_ramlist()
rcu_read_lock()
...
qemu_mutex_unlock_ramlist()
...
rcu_read_unlock()
Backports the write barriers from commit 0dc3f44aca18b1be8b425f3f4feb4b3e8d68de2e in qemu
Coverity flags this as "dereference after null check". Not quite a
dereference, since it will just EFAULT, but still nice to fix.
Backports commit a904c91196a9c5dbd7b9abcd3d40b0824286fb1c from qemu
The TARGET_HAS_ICE #define is intended to indicate whether a target-*
guest CPU implementation supports the breakpoint handling. However,
all our guest CPUs have that support (the only two which do not
define TARGET_HAS_ICE are unicore32 and openrisc, and in both those
cases the bp support is present and the lack of the #define is just
a bug). So remove the #define entirely: all new guest CPU support
should include breakpoint handling as part of the basic implementation.
Backports commit ec53b45bcd1f74f7a4c31331fa6d50b402cd6d26 from qemu
host pointer accesses force pointer math, let's
add a wrapper to make them safer.
Backports relevant parts of commit 1240be24357ee292f8d05aa2abfdba75dd0ca25d from qemu
Otherwise fw_cfg accesses are split into 4-byte ones before they reach the
fw_cfg ops / handlers.
Backports commit ff6cff7554be06e95f8d712f66cd16bd6681c746 from qemu
Loading the BIOS in the mac99 machine is interesting, because there is a
PROM in the middle of the BIOS region (from 16K to 32K). Before memory
region accesses were clamped, when QEMU was asked to load a BIOS from
0xfff00000 to 0xffffffff it would put even those 16K from the BIOS file
into the region. This is weird because those 16K were not actually
visible between 0xfff04000 and 0xfff07fff. However, it worked.
After clamping was added, this also worked. In this case, the
cpu_physical_memory_write_rom_internal function split the write in
three parts: the first 16K were copied, the PROM area (second 16K) were
ignored, then the rest was copied.
Problems then started with commit 965eb2f (exec: do not clamp accesses
to MMIO regions, 2015-06-17). Clamping accesses is not done for MMIO
regions because they can overlap wildly, and MMIO registers can be
expected to perform full-width accesses based only on their address
(with no respect for adjacent registers that could decode to completely
different MemoryRegions). However, this lack of clamping also applied
to the PROM area! cpu_physical_memory_write_rom_internal thus failed
to copy the third range above, i.e. only copied the first 16K of the BIOS.
In effect, address_space_translate is expecting _something else_ to do
the clamping for MMIO regions if the incoming length is large. This
"something else" is memory_access_size in the case of address_space_rw,
so use the same logic in cpu_physical_memory_write_rom_internal.
Backports commit b242e0e0e2969c044a318e56f7988bbd84de1f63 from qemu
Because the clamping was done against the MemoryRegion,
address_space_rw was effectively broken if a write spanned
multiple sections that are not linear in underlying memory
(with the memory not being under an IOMMU).
This is visible with the MIPS rc4030 IOMMU, which is implemented
as a series of alias memory regions that point to the actual RAM.
Backports commit e4a511f8cc6f4a46d409fb5c9f72c38ba45f8d83 from qemu
It is common for MMIO registers to overlap, for example a 4 byte register
at 0xcf8 (totally random choice... :)) and a 1 byte register at 0xcf9.
If these registers are implemented via separate MemoryRegions, it is
wrong to clamp the accesses as the value written would be truncated.
Hence for these regions the effects of commit 23820db (exec: Respect
as_translate_internal length clamp, 2015-03-16, previously applied as
commit c3c1bb9) must be skipped.
Backports commit 965eb2fcdfe919ecced6c34803535ad32dc1249c from qemu
This will either create a new AS or return a pointer to an
already existing equivalent one, if we have already created
an AS for the specified root memory region.
The motivation is to reuse address spaces as much as possible.
It's going to be quite common that bus masters out in device land
have pointers to the same memory region for their mastering yet
each will need to create its own address space. Let the memory
API implement sharing for them.
Aside from the perf optimisations, this should reduce the amount
of redundant output on info mtree as well.
Thee returned value will be malloced, but the malloc will be
automatically freed when the AS runs out of refs.
Backports commit f0c02d15b57da6f5463e3768aa0cfeedccf4b8f4 from qemu
Use cpu_get_phys_page_attrs_debug() when doing virtual-to-physical
conversions in debug related code, so that we can obtain the right
address space index and thus select the correct AddressSpace,
rather than always using cpu->as.
Backports commit 5232e4c798ba7a46261d3157b73d08fc598e7dcb from qemu
Add a function to return the AddressSpace for a CPU based on
its numerical index. (Callers outside exec.c don't have access
to the CPUAddressSpace struct so can't just fish it out of the
CPUState struct directly.)
Backports commit 651a5bc03705102de519ebf079a40ecc1da991db from qemu
Pass the MemTxAttrs for the memory access to iotlb_to_region(); this
allows it to determine the correct AddressSpace to use for the lookup.
Backports commit a54c87b68a0410d0cf6f8b84e42074a5cf463732 from qemu
When looking up the MemoryRegionSection for the new TLB entry in
tlb_set_page_with_attrs(), use cpu_asidx_from_attrs() to determine
the correct address space index for the lookup, and pass it into
address_space_translate_for_iotlb().
Backports commit d7898cda81b6efa6b2d7a749882695cdcf280eaa from qemu
Add a new method to CPUClass which the memory system core can
use to obtain the correct address space index to use for a memory
access with a given set of transaction attributes, together
with the wrapper function cpu_asidx_from_attrs() which implements
the default behaviour ("always use asidx 0") for CPU classes
which don't provide the method.
Backports commit d7f25a9e6a6b2c69a0be6033903b7d6087bcf47d from qemu
Add a new optional method get_phys_page_attrs_debug() to CPUClass.
This is like the existing get_phys_page_debug(), but also returns
the memory transaction attributes to use for the access.
This will be necessary for CPUs which have multiple address
spaces and use the attributes to select the correct address
space.
We provide a wrapper function cpu_get_phys_page_attrs_debug()
which falls back to the existing get_phys_page_debug(), so we
don't need to change every target CPU.
Backports commit 1dc6fb1f5cc5cea5ba01010a19c6acefd0ae4b73 from qemu
Allow multiple calls to cpu_address_space_init(); each
call adds an entry to the cpu->ases array at the specified
index. It is up to the target-specific CPU code to actually use
these extra address spaces.
Since this multiple AddressSpace support won't work with
KVM, add an assertion to avoid confusing failures.
Backports commit 12ebc9a76dd7702aef0a3618717a826c19c34ef4 from qemu
Rather than setting cpu->as unconditionally in cpu_exec_init
(and then having target-i386 override this later), don't set
it until the first call to cpu_address_space_init.
This requires us to initialise the address space for
both TCG and KVM (KVM doesn't need the AS listener but
it does require cpu->as to be set).
For target CPUs which don't set up any address spaces (currently
everything except i386), add the default address_space_memory
in qemu_init_vcpu().
Backports commit 56943e8cc14b7eeeab67d1942fa5d8bcafe3e53f from qemu
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Backports commit 12b167226f2804063cf8d72fe4fdc01764c99e96 from qemu
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Backports commit 74c21bd07491739c6e56bcb1f962e4df730e77f3 from qemu
Convert the SPARC CPU from cpu_load/save functions to VMStateDescription.
We preserve migration compatibility with the previous version
(required for SPARC32 but not necessarily for SPARC64).
Backports commit df32c8d436d4eb3f40b00647ca0df2bbc7f6bf6f from qemu
For inbound migration we really want to be able to set the PSR without
having any side effects, but cpu_put_psr() calls cpu_check_irqs() which
might try to deliver CPU interrupts. Split cpu_put_psr() into the
no-side-effect and side-effect parts.
This includes reordering the cpu_check_irqs() to the end of cpu_put_psr(),
because that function may actually end up calling cpu_interrupt(), which
does not seem like a good thing to happen in the middle of updating the PSR.
Backports commit 4552a09dd4055c806b7df8c595dc0fb8951834be from qemu
x86_cpu_handle_mmu_fault is currently checking twice for writability
and executability of pages; the first time to decide whether to
trigger a page fault, the second time to compute the "prot" argument
to tlb_set_page_with_attrs.
Reorganize code so that first "prot" is computed, then it is used
to check whether to raise a page fault, then finally PROT_WRITE is
removed if the D bit will have to be set.
Backports commit 76c64d33601a4948d6f72022992574a75b6fab97 from qemu
arm_regime_using_lpae_format checks whether the LPAE extension is used
for stage 1 translation regimes. MMU indexes not exclusively of a stage 1
regime won't work with this method.
In case of ARMMMUIdx_S12NSE0 or ARMMMUIdx_S12NSE1, offset these values
by ARMMMUIdx_S1NSE0 to get the right index indicating a stage 1
translation regime.
Rename also the function to arm_s1_regime_using_lpae_format and update
the comments to reflect the change.
Backports commit deb2db996cbb9470b39ae1e383791ef34c4eb3c2 from qemu
Our use of glib is now pervasive across QEMU. Move the include of glib-compat.h
from qemu-common.h to osdep.h so that it is more widely accessible and doesn't
get forgotten by accident. (Failure to include it will result in build failure
on old versions of glib which is likely to be unnoticed by most developers.)
Backports commit 529490e5d664a20d5c4223070dd7c03a0e02b6bd from qemu
memcpy can take a large amount of time for small reads and writes.
Handle the common case of reading s/g descriptors from memory (there
is no corresponding "write" case that is as common, because writes
often use address_space_st* functions) by inlining the relevant
parts of address_space_read into the caller.
Backports commit 3cc8f884996584630734a90c9b3c535af81e3c92 from qemu
We want to inline the case where there is only one iteration, because
then the compiler can also inline the memcpy. As a start, extract
everything after the first address_space_translate call.
Backports commit a203ac702e0720135fac8b1f2061d119814c1798 from qemu
Rather than dispatching on is_write for every iteration, make
address_space_rw call one of the two functions. The amount of
duplicate logic is pretty small, and memory_access_is_direct can
be tweaked so that it inlines better in the callers.
Backports commit eb7eeb88628074207dd611472e712af775985e73 from qemu
For the common case of DMA into non-hotplugged RAM, it is unnecessary
but expensive to do object_ref/unref. Add back an owner field to
MemoryRegion, so that these memory regions can skip the reference
counting.
Backports commit 612263cf33062f7441a5d0e3b37c65991fdc3210 from qemu
Order fields so that all fields accessed during a RAM read/write fit in
the same cache line.
Backports commit a676854f3447019c7c4b005ab6aece905fccfddd from qemu
The function is equivalent to memory_region_destructor_ram(), so
it's not needed anymore.
Backports commit fc3e7665d7fe1b2f842441d250d7afec26b8a910 from qemu
Replace qemu_ram_free_from_ptr() with qemu_ram_free().
The only difference between qemu_ram_free_from_ptr() and
qemu_ram_free() is that g_free_rcu() is used instead of
call_rcu(reclaim_ramblock). We can safely replace it because:
* RAM blocks allocated by qemu_ram_alloc_from_ptr() always have
RAM_PREALLOC set;
* reclaim_ramblock(block) will do nothing except g_free(block)
if RAM_PREALLOC is set at block->flags.
Backports commit a29ac16632aec6065c72985b9f7eeb1ca6fbef4a from qemu
Qemu does not generally perform alignment checks. However, the ARM ARM
requires implementation of alignment exceptions for a number of cases
including LDREX, and Windows-on-ARM relies on this.
This change adds plumbing to enable alignment checks on loads using
MO_ALIGN, a do_unaligned_access hook to raise the exception (data
abort), and uses the new aligned loads in LDREX (for all but
single-byte loads).
Backports commit 30901475b91ef1f46304404ab4bfe89097f61b96 from qemu
LEON3 allows the CASA instruction to be used from user space
if the ASI is set to 0xa (user data).
Backports commit bd4e097a8e30bb63ed7f46553b13f60809c30ac3 from qemu
"Please keep this list in alphabetical order" has been more honoured
in the breach than in the observance. Clean up.
While there, drop a redundant struct declaration.
Backports commit 2988cbeaf94203b2cf31c0b3f589aa4ebc0cff34 from qemu
Anthony reported that >4GB guests on Xen with 32bit QEMU broke after
commit 4ed023c ("Round up RAMBlock sizes to host page sizes", 2015-11-05).
In that patch sizes are masked against qemu_host_page_size/mask which
are uintptr_t, and thus 32bit on a 32bit QEMU, even though the ram space
might be bigger than 4GB on Xen.
Since ram_addr_t is not available on user-mode emulation targets, ensure
that we get a sign extension when masking away the low bits of the address.
Remove the ~10 year old scary comment that the type of these variables
is probably wrong, with another equally scary comment. The new comment
however does not have "???" in it, which is arguably an improvement.
For completeness use the alignment macros in linux-user and bsd-user
instead of manually doing an &. linux-user and bsd-user are not affected
by the Xen issue, however.
Backports commit 0c2d70c448b7853a91cfa63659aa3cc6630fb9be from qemu
memory_region_unref(mr) can free memory.
For example I got:
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f43280d4700 (LWP 4462)]
0x00007f43323283c0 in phys_section_destroy (mr=0x7f43259468b0)
at /home/don/xen/tools/qemu-xen-dir/exec.c:1023
1023 if (mr->subpage) {
(gdb) bt
at /home/don/xen/tools/qemu-xen-dir/exec.c:1023
at /home/don/xen/tools/qemu-xen-dir/exec.c:1034
at /home/don/xen/tools/qemu-xen-dir/exec.c:2205
(gdb) p mr
$1 = (MemoryRegion *) 0x7f43259468b0
And this change prevents this.
Backports commit 55b4e80b047300e1512df02887b7448ba3786b62 from qemu
getpagesize on Linux returns an int. Fix QEMU's implementation for
Windows to return an int (instead of size_t), too.
This fixes a compiler warning which was introduced recently
(commit 093e3c42).
Backports commit a28c2f2df7679e3a87789e9fb7ed69331f697297 from qemu
This is reported by Coverity. The algorithm description at
ftp://ftp.icm.edu.pl/packages/ggi/doc/hw/sparc/Sparc.pdf suggests
that the 32-bit parts of rs2, after the left shift, is treated
as a 64-bit integer. Bits 32 and above are used to do the
saturating truncation.
Backports commit 12a3567c4099be194b44987ac5d7d65b99bcfab7 from qemu
CP0.Status.KX/SX/UX bits are responsible for enabling access to 64-bit
Kernel/Supervisor/User Segments. If bit is cleared an access to
corresponding segment should generate Address Error Exception.
However, the guest may still be able to access some pages belonging to
the disabled 64-bit segment because we forget to flush QEMU TLB.
This patch fixes it.
Backports commit f93c3a8d0c0c1038dbe1e957eb8ab92671137975 from qemu
