324b2298fe
Apart from targets.rst, which was written by hand, this is an automated
conversion obtained with the following command:
makeinfo --force -o - --docbook \
-D 'qemu_system_x86 QEMU_SYSTEM_X86_MACRO' \
-D 'qemu_system QEMU_SYSTEM_MACRO' \
$texi | pandoc -f docbook -t rst+smart | perl -e '
$/=undef;
$_ = <>;
s/^- − /- /gm;
s/QEMU_SYSTEM_MACRO/|qemu_system|/g;
s/QEMU_SYSTEM_X86_MACRO/|qemu_system_x86|/g;
s/(?=::\n\n +\|qemu)/.. parsed-literal/g;
s/:\n\n::$/::/gm;
print' > $rst
In addition, the following changes were made manually:
- target-i386.rst and target-mips.rst: replace CPU model documentation with
an include directive
- monitor.rst: replace the command section with a comment
- images.rst: add toctree
- target-arm.rst: Replace use of :math: (which Sphinx complains
about) with :sup:, and hide it behind |I2C| and |I2C| substitutions.
Content that is not @included remains exclusive to qemu-doc.texi.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200228153619.9906-20-peter.maydell@linaro.org
Message-id: 20200226113034.6741-19-pbonzini@redhat.com
[PMM: Fixed target-arm.rst use of :math:; remove out of date
note about images.rst from commit message; fixed expansion
of |qemu_system_x86|; use parsed-literal in invocation.rst
when we want to use |qemu_system_x86|; fix incorrect subsection
level for "OS requirements" in target-i386.rst; fix incorrect
syntax for making links to other sections of the manual]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
82 lines
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82 lines
2.4 KiB
ReStructuredText
.. _gdb_005fusage:
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GDB usage
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---------
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QEMU has a primitive support to work with gdb, so that you can do
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'Ctrl-C' while the virtual machine is running and inspect its state.
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In order to use gdb, launch QEMU with the '-s' option. It will wait for
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a gdb connection:
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.. parsed-literal::
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|qemu_system| -s -kernel bzImage -hda rootdisk.img -append "root=/dev/hda"
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Connected to host network interface: tun0
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Waiting gdb connection on port 1234
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Then launch gdb on the 'vmlinux' executable::
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> gdb vmlinux
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In gdb, connect to QEMU::
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(gdb) target remote localhost:1234
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Then you can use gdb normally. For example, type 'c' to launch the
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kernel::
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(gdb) c
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Here are some useful tips in order to use gdb on system code:
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1. Use ``info reg`` to display all the CPU registers.
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2. Use ``x/10i $eip`` to display the code at the PC position.
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3. Use ``set architecture i8086`` to dump 16 bit code. Then use
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``x/10i $cs*16+$eip`` to dump the code at the PC position.
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Advanced debugging options:
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The default single stepping behavior is step with the IRQs and timer
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service routines off. It is set this way because when gdb executes a
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single step it expects to advance beyond the current instruction. With
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the IRQs and timer service routines on, a single step might jump into
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the one of the interrupt or exception vectors instead of executing the
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current instruction. This means you may hit the same breakpoint a number
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of times before executing the instruction gdb wants to have executed.
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Because there are rare circumstances where you want to single step into
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an interrupt vector the behavior can be controlled from GDB. There are
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three commands you can query and set the single step behavior:
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``maintenance packet qqemu.sstepbits``
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This will display the MASK bits used to control the single stepping
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IE:
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::
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(gdb) maintenance packet qqemu.sstepbits
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sending: "qqemu.sstepbits"
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received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
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``maintenance packet qqemu.sstep``
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This will display the current value of the mask used when single
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stepping IE:
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::
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(gdb) maintenance packet qqemu.sstep
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sending: "qqemu.sstep"
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received: "0x7"
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``maintenance packet Qqemu.sstep=HEX_VALUE``
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This will change the single step mask, so if wanted to enable IRQs on
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the single step, but not timers, you would use:
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::
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(gdb) maintenance packet Qqemu.sstep=0x5
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sending: "qemu.sstep=0x5"
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received: "OK"
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