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3 commits

Author SHA1 Message Date
Michael Ellerman
bad194550f powerpc/xmon: Fix disassembly CPU feature checks
[ Upstream commit 14196e47c5ffe32af7ed5a51c9e421c5ea5bccce ]

In the xmon disassembly code there are several CPU feature checks to
determine what dialects should be passed to the disassembler. The
dialect controls which instructions the disassembler will recognise.

Unfortunately the checks are incorrect, because instead of passing a
single CPU feature they are passing a mask of feature bits.

For example the code:

  if (cpu_has_feature(CPU_FTRS_POWER5))
      dialect |= PPC_OPCODE_POWER5;

Is trying to check if the system is running on a Power5 CPU. But
CPU_FTRS_POWER5 is a mask of *all* the feature bits that are enabled on
a Power5.

In practice the test will always return true for any 64-bit CPU, because
at least one bit in the mask will be present in the CPU_FTRS_ALWAYS
mask.

Similarly for all the other checks against CPU_FTRS_xx masks.

Rather than trying to match the disassembly behaviour exactly to the
current CPU, just differentiate between 32-bit and 64-bit, and Altivec,
VSX and HTM.

That will cause some instructions to be shown in disassembly even
on a CPU that doesn't support them, but that's OK, objdump -d output
has the same behaviour, and if anything it's less confusing than some
instructions not being disassembled.

Fixes: 897f112bb42e ("[POWERPC] Import updated version of ppc disassembly code for xmon")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240509121248.270878-2-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:10 +01:00
Greg Kurz
ea44f2fc55 powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
[ Upstream commit 8873aab8646194a4446117bb617cc71bddda2dee ]

All these commands end up peeking into the PACA using the user
originated cpu id as an index. Check the cpu id is valid in order
to prevent xmon to crash. Instead of printing an error, this follows
the same behavior as the "lp s #" command : ignore the buggy cpu id
parameter and fall back to the #-less version of the command.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/161531347060.252863.10490063933688958044.stgit@bahia.lan
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:41 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00