Re: [PATCH 1/2] iommu/mediatek-v1: Alloc building as module

From: Robin Murphy
Date: Thu Mar 25 2021 - 13:42:56 EST


^^Nit: presumably you meant "Allow" in the subject.

On 2021-03-25 17:16, Will Deacon wrote:
On Tue, Mar 23, 2021 at 01:58:00PM +0800, Yong Wu wrote:
This patch only adds support for building the IOMMU-v1 driver as module.
Correspondingly switch the config to tristate.

Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
rebase on v5.12-rc2.
---
drivers/iommu/Kconfig | 2 +-
drivers/iommu/mtk_iommu_v1.c | 9 ++++-----
2 files changed, 5 insertions(+), 6 deletions(-)

Both of these patches look fine to me, but you probably need to check
the setting of MODULE_OWNER after:

https://lore.kernel.org/r/f4de29d8330981301c1935e667b507254a2691ae.1616157612.git.robin.murphy@xxxxxxx

Right, furthermore I would rather expect these patches on their own to hit the problem that my patch tries to avoid - where since mtk_iommu_ops is const, the current version of iommu_device_set_ops() is liable to blow up trying to write to rodata.

In fact I do wonder a little why that wasn't happening already - maybe the compiler is clever enough to tell that the assignment is redundant when THIS_MODULE == 0, and elides it :/

Robin.