Re: Linux 5.1.9 build failure with CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT=n

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Jun 11, 2019 at 03:56:35PM +0200, Sven Joachim wrote:
> Commit 1e07d63749 ("drm/nouveau: add kconfig option to turn off nouveau
> legacy contexts. (v3)") has caused a build failure for me when I
> actually tried that option (CONFIG_NOUVEAU_LEGACY_CTX_SUPPORT=n):
> 
> ,----
> | Kernel: arch/x86/boot/bzImage is ready  (#1)
> |   Building modules, stage 2.
> |   MODPOST 290 modules
> | ERROR: "drm_legacy_mmap" [drivers/gpu/drm/nouveau/nouveau.ko] undefined!
> | scripts/Makefile.modpost:91: recipe for target '__modpost' failed
> `----
> 
> Upstream does not have that problem, as commit bed2dd8421 ("drm/ttm:
> Quick-test mmap offset in ttm_bo_mmap()") has removed the use of
> drm_legacy_mmap from nouveau_ttm.c.  Unfortunately that commit does not
> apply in 5.1.9.
> 
> Most likely 4.19.50 and 4.14.125 are also affected, I haven't tested
> them yet.

They probably are.

Should I just revert this patch in the stable tree, or add some other
patch (like the one pointed out here, which seems an odd patch for
stable...)

thanks,

greg k-h