Re: [RFC PATCH 08/12] KVM: TDX: Use atomic64_dec_return() instead of a poor equivalent

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 2025-08-28 at 15:33 -0700, Sean Christopherson wrote:
> On Thu, Aug 28, 2025, Rick P Edgecombe wrote:
> > On Thu, 2025-08-28 at 14:48 +0800, Yan Zhao wrote:
> > > Hmm, I still think it's safer to keep the nr_premapped to detect any unexpected
> > > code change.
> > 
> > When I checking patch 6 I saw how many more KVM_BUG_ON()s we ended up with in
> > TDX code compared to the rest of KVM. (even after we dropped a bunch during
> > development) We have to differentiate from good safety, and "safety" that is
> > really just propping up brittle code. Each KVM_BUG_ON() is a hint that there
> > might be design issues.
> 
> Nah, I think we're good.  The majority of the asserts are on SEAMCALLs, and those
> are no different than the WARN_ONCE() in vmx_insn_failed(), just spread out to
> individual call sites.
> 
> Once those are out of the numbers are entirely reasonable (WARNs and KVM_BUG_ON
> are both assertions against bugs, one is just guaranteed to be fatal to the VM).
> 
>   $ git grep -e KVM_BUG_ON -e WARN_ vmx/tdx.c | wc -l
>   25
>   $ git grep -e KVM_BUG_ON -e WARN_  | wc -l
>   459

Hmm, ok.




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux