It's either "GNU *Library* General Public version 2" or "GNU Lesser
General Public version *2.1*", but there was no "version 2.0" of the
"Lesser" library. So assume that version 2.1 is meant here.
Backports commit fb0343d5b4dd4b9b9e96e563d913a3e0c709fe4e from qemu
In icount mode, instructions that access io memory spaces in the middle
of the translation block invoke TB recompilation. After recompilation,
such instructions become last in the TB and are allowed to access io
memory spaces.
When the code includes instruction like i386 'xchg eax, 0xffffd080'
which accesses APIC, QEMU goes into an infinite loop of the recompilation.
This instruction includes two memory accesses - one read and one write.
After the first access, APIC calls cpu_report_tpr_access, which restores
the CPU state to get the current eip. But cpu_restore_state_from_tb
resets the cpu->can_do_io flag which makes the second memory access invalid.
Therefore the second memory access causes a recompilation of the block.
Then these operations repeat again and again.
This patch moves resetting cpu->can_do_io flag from
cpu_restore_state_from_tb to cpu_loop_exit* functions.
It also adds a parameter for cpu_restore_state which controls restoring
icount. There is no need to restore icount when we only query CPU state
without breaking the TB. Restoring it in such cases leads to the
incorrect flow of the virtual time.
In most cases new parameter is true (icount should be recalculated).
But there are two cases in i386 and openrisc when the CPU state is only
queried without the need to break the TB. This patch fixes both of
these cases.
Backports commit afd46fcad2dceffda35c0586f5723c127b6e09d8 from qemu
move tcg-runtime.c, translate-all.(ch) and translate-common.c into
accel/tcg/ subdirectory and updated related trace-events file.
Backports commit 244f144134d0dd182f1af8654e7f9a79fe770368 and applies
relevant changes made in db432672dc50ed86dda17ac821b7eb07411a90af and
d9bb58e51068dfc48746c6af0179926c8dc05bce from qemu