Hi Andrew,
On 9/6/19 6:20 PM, Andrew Cooper wrote:
On 06/09/2019 17:00, Arnd Bergmann wrote:
On Fri, Sep 6, 2019 at 5:55 PM Andrew Cooper <andrew.coop...@citrix.com> wrote:
On 06/09/2019 16:39, Arnd Bergmann wrote:
HYPERVISOR_platform_op() is an inline function and should not
be exported. Since commit 15bfc2348d54 ("modpost: check for
static EXPORT_SYMBOL* functions"), this causes a warning:
WARNING: "HYPERVISOR_platform_op" [vmlinux] is a static EXPORT_SYMBOL_GPL
Remove the extraneous export.
Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions")
Signed-off-by: Arnd Bergmann <a...@arndb.de>
Something is wonky. That symbol is (/ really ought to be) in the
hypercall page and most definitely not inline.
Which tree is that changeset from? I can't find the SHA.
This is from linux-next, I think from the kbuild tree.
Thanks.
Julien/Stefano: Why are any of these hypercalls out-of-line? ARM
doesn't use the hypercall page, and there is no argument translation
(not even in arm32 as there are no 5-argument hypercalls declared).
I am not sure how the hypercall page makes things different. You still
have to store the arguments in the correct register so...
They'd surely be easier to implement with a few static inlines and some
common code, than to try and replicate the x86 side hypercall_page
interface ?
... I don't think they will be easier to implement with a few static
inlines. The implementation will likely end up to be similar to
arch/x86/asm/xen/hypercall.h.
Furthermore, one of the downside of per-arch static inline is it is more
difficult to ensure the prototype match for all the architectures.
Although, it might be possible to make them common by only requesting
per-arch to implement HYPERCALL_N(...).
So I think the code is better as it is.
While looking at the code, I also realized that the implementation of
HYPERCALL_dm_op might be incorrect for Arm32. Similarly do privcmd call,
I think dm_op call should enable user access as they will be used by
userspace.
We don't use dm_op on Arm so far, hence why I think this was unnoticed.
I will see if I can reproduce it and send a patch.
Cheers,
--
Julien Grall
