x86/ldt: Remove unused variable in map_ldt_struct()

Splitting out the sanity check in map_ldt_struct() moved page table syncing
into a separate function, which made the pgd variable unused. Remove it.

[ tglx: Massaged changelog ]

Fixes: 9bae3197e15d ("x86/ldt: Split out sanity check in map_ldt_struct()")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: peterz@infradead.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: bhe@redhat.com
Cc: willy@infradead.org
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181026122856.66224-4-kirill.shutemov@linux.intel.com

diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index 18e4525..6135ae8 100644 (file)
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -207,7 +207,6 @@ map_ldt_struct(struct mm_struct *mm, struct ldt_struct *ldt, int slot)
        bool is_vmalloc;
        spinlock_t *ptl;
        int i, nr_pages;
-       pgd_t *pgd;
 
        if (!static_cpu_has(X86_FEATURE_PTI))
                return 0;
@@ -221,13 +220,6 @@ map_ldt_struct(struct mm_struct *mm, struct ldt_struct *ldt, int slot)
        /* Check if the current mappings are sane */
        sanity_check_ldt_mapping(mm);
 
-       /*
-        * Did we already have the top level entry allocated?  We can't
-        * use pgd_none() for this because it doens't do anything on
-        * 4-level page table kernels.
-        */
-       pgd = pgd_offset(mm, LDT_BASE_ADDR);
-
        is_vmalloc = is_vmalloc_addr(ldt->entries);
 
        nr_pages = DIV_ROUND_UP(ldt->nr_entries * LDT_ENTRY_SIZE, PAGE_SIZE);