Re: [PULL 30/33] tcg: Allocate sufficient storage in temp_allocate_frame

[Richard W.M. Jones]

On Sat, Jun 19, 2021 at 11:14:49AM -0700, Richard Henderson wrote:
> This function should have been updated for vector types
> when they were introduced.
> 
> Fixes: d2fd745fe8b
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/367
> Cc: qemu-stable@nongnu.org
> Tested-by: Stefan Weil <sw@weilnetz.de>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  tcg/tcg.c | 32 +++++++++++++++++++++++++++-----
>  1 file changed, 27 insertions(+), 5 deletions(-)
> 
...
> +    assert(align <= TCG_TARGET_STACK_ALIGN);

This assertion is triggering:
https://bugzilla.redhat.com/show_bug.cgi?id=1999878

It happens when the kernel is booting after this line:

  [    7.315373] Loading compiled-in X.509 certificates

If everything was working then the next line of output *should* be:

  Loaded X.509 cert 'Fedora kernel signing key: 
65d4930f94e951d5c1531017b9559872a4e7b0b0'

but instead it is:

  [    7.183521] ThumbEE CPU extension supported.
  [    7.186066] Registering SWP/SWPB emulation handler
  [    7.304374] registered taskstats version 1
  [    7.315373] Loading compiled-in X.509 certificates
  qemu-system-arm: ../tcg/tcg.c:3063: temp_allocate_frame: Assertion `align <= 
TCG_TARGET_STACK_ALIGN' failed.

Unfortunately I don't have an easy reproducer.  It reproduces very
reliably in Fedora's build system (qemu 6.1.0 running a TCG armv7 L2
guest on armv7 L1 host on unknown aarch64 L0 host).  But my attempts
to perform the same operation anywhere else don't reproduce the
problem.

What does the assertion mean?

Rich.

-- 
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