Re: [PATCH] x86/paravirt: Fix tlb_remove_table function callback prototype warning

[Kees Cook]

On Wed, 26 Jul 2023 16:11:43 -0700, Kees Cook wrote:
> Under W=1, this warning is visible in Clang 16 and newer:
> 
> arch/x86/kernel/paravirt.c:337:4: warning: cast from 'void (*)(struct 
> mmu_gather *, struct page *)' to 'void (*)(struct mmu_gather *, void *)' 
> converts to incompatible function type [-Wcast-function-type-strict]
>(void (*)(struct mmu_gather *, void 
> *))tlb_remove_page,
>
> ^~
> 
> Add a direct wrapper instead, which will make this warning (and
> potential KCFI failures) go away.
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] x86/paravirt: Fix tlb_remove_table function callback prototype warning
  https://git.kernel.org/kees/c/fcce1c6cb156

Take care,

-- 
Kees Cook

___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Re: [PATCH] x86/paravirt: Fix tlb_remove_table function callback prototype warning

[Juergen Gross via Virtualization]

On 27.07.23 01:11, Kees Cook wrote:

Under W=1, this warning is visible in Clang 16 and newer:

arch/x86/kernel/paravirt.c:337:4: warning: cast from 'void (*)(struct 
mmu_gather *, struct page *)' to 'void (*)(struct mmu_gather *, void *)' 
converts to incompatible function type [-Wcast-function-type-strict]
(void (*)(struct mmu_gather *, void 
*))tlb_remove_page,

^~

Add a direct wrapper instead, which will make this warning (and
potential KCFI failures) go away.

Reported-by: kernel test robot 
Closes: 
https://lore.kernel.org/oe-kbuild-all/202307260332.pjntwr6o-...@intel.com/
Cc: Juergen Gross 
Cc: Peter Zijlstra 
Cc: Sami Tolvanen 
Cc: Nathan Chancellor 
Cc: Ajay Kaher 
Cc: Alexey Makhalov 
Cc: VMware PV-Drivers Reviewers 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Kees Cook 


Reviewed-by: Juergen Gross 


Juergen



OpenPGP_0xB0DE9DD628BF132F.asc
Description: OpenPGP public key


OpenPGP_signature
Description: OpenPGP digital signature
___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

[PATCH] x86/paravirt: Fix tlb_remove_table function callback prototype warning

[Kees Cook]

Under W=1, this warning is visible in Clang 16 and newer:

arch/x86/kernel/paravirt.c:337:4: warning: cast from 'void (*)(struct 
mmu_gather *, struct page *)' to 'void (*)(struct mmu_gather *, void *)' 
converts to incompatible function type [-Wcast-function-type-strict]
   (void (*)(struct mmu_gather *, void 
*))tlb_remove_page,
   
^~

Add a direct wrapper instead, which will make this warning (and
potential KCFI failures) go away.

Reported-by: kernel test robot 
Closes: 
https://lore.kernel.org/oe-kbuild-all/202307260332.pjntwr6o-...@intel.com/
Cc: Juergen Gross 
Cc: Peter Zijlstra 
Cc: Sami Tolvanen 
Cc: Nathan Chancellor 
Cc: Ajay Kaher 
Cc: Alexey Makhalov 
Cc: VMware PV-Drivers Reviewers 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Kees Cook 
---
 arch/x86/kernel/paravirt.c | 8 ++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index ac10b46c5832..23d4d7114473 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -79,6 +79,11 @@ void __init native_pv_lock_init(void)
static_branch_disable(_spin_lock_key);
 }
 
+static void native_tlb_remove_table(struct mmu_gather *tlb, void *table)
+{
+   tlb_remove_page(tlb, table);
+}
+
 unsigned int paravirt_patch(u8 type, void *insn_buff, unsigned long addr,
unsigned int len)
 {
@@ -295,8 +300,7 @@ struct paravirt_patch_template pv_ops = {
.mmu.flush_tlb_kernel   = native_flush_tlb_global,
.mmu.flush_tlb_one_user = native_flush_tlb_one_user,
.mmu.flush_tlb_multi= native_flush_tlb_multi,
-   .mmu.tlb_remove_table   =
-   (void (*)(struct mmu_gather *, void *))tlb_remove_page,
+   .mmu.tlb_remove_table   = native_tlb_remove_table,
 
.mmu.exit_mmap  = paravirt_nop,
.mmu.notify_page_enc_status_changed = paravirt_nop,
-- 
2.34.1

___
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization