Possible regression by ab037dd87a2f (powerpc/vdso: Switch VDSO to generic C implementation.)

Tue Jul 27 18:45:48 AEST 2021

Dear Christophe,

On ppc64le Go 1.16.2 from Ubuntu 21.04 terminates with a segmentation 
fault [1], and it might be related to *[release-branch.go1.16] runtime: 
fix crash during VDSO calls on PowerPC* [2], conjecturing that commit 
ab037dd87a2f (powerpc/vdso: Switch VDSO to generic C implementation.) 
added in Linux 5.11 causes this.

If this is indeed the case, this would be a regression in userspace. Is 
there a generic fix or should the change be reverted?

Kind regards,

Paul

[1]: https://github.com/9elements/converged-security-suite/issues/268
[2]: https://go-review.googlesource.com/c/go/+/334410/
[3]: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ab037dd87a2f946556850e204c06cbd7a2a19390