x86/paravirt: Fix tlb_remove_table function callback prototype warning

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 <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307260332.pJntWR6o-lkp@intel.com/
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Alexey Makhalov <amakhalov@vmware.com>
Cc: VMware PV-Drivers Reviewers <pv-drivers@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: virtualization@lists.linux-foundation.org
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20230726231139.never.601-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index ac10b46c5832bf9f57ababa615903e877bd8f02a..23d4d71144732a52af6bf4341041b87306ab6286 100644 (file)
--- 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(&virt_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,