Regression on linux-next (next-20250321)

[Jason Gunthorpe]

On Tue, Mar 25, 2025 at 12:40:16AM -0700, Nicolin Chen wrote:
> 
> On Tue, Mar 25, 2025 at 05:39:39AM +0000, Borah, Chaitanya Kumar wrote:
> > Hello Nicolin,
> > 
> > Hope you are doing well. I am Chaitanya from the linux graphics team in Intel.
> > 
> > This mail is regarding a regression we are seeing in our CI runs[1] on linux-next repository.
> > 
> > Since the version next-20250321 [2], we are seeing the following regression
> > 
> > `````````````````````````````````````````````````````````````````````````````````
> > <4>[    0.226495] Unpatched return thunk in use. This should not happen!
> > <4>[    0.226502] WARNING: CPU: 0 PID: 1 at arch/x86/kernel/cpu/bugs.c:3107 __warn_thunk+0x62/0x70
> 
> Hmm....I wonder why x86 can be affected...

I wonder if this is realted to the objtool warning Steven reported:

https://lore.kernel.org/linux-next/20250321193600.2bfe03bb@canb.auug.org.au/

vmlinux.o: warning: objtool: iommu_dma_get_msi_page() falls through to next function __iommu_dma_unmap()

I have no idea what either error means or how to fix it. AFAICT there
is nothing special about this patch to trigger this?

+Peter & Josh

Jason