sparc64: Fix illegal relative branches in hypervisor patched TLB code.

[ Upstream commit b429ae4d5b565a71dfffd759dfcd4f6c093ced94 ]

When we copy code over to patch another piece of code, we can only use
PC-relative branches that target code within that piece of code.

Such PC-relative branches cannot be made to external symbols because
the patch moves the location of the code and thus modifies the
relative address of external symbols.

Use an absolute jmpl to fix this problem.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/sparc/mm/ultra.S b/arch/sparc/mm/ultra.S
index b4f4733..85de139 100644 (file)
--- a/arch/sparc/mm/ultra.S
+++ b/arch/sparc/mm/ultra.S
@@ -30,7 +30,7 @@
        .text
        .align          32
        .globl          __flush_tlb_mm
-__flush_tlb_mm:                /* 18 insns */
+__flush_tlb_mm:                /* 19 insns */
        /* %o0=(ctx & TAG_CONTEXT_BITS), %o1=SECONDARY_CONTEXT */
        ldxa            [%o1] ASI_DMMU, %g2
        cmp             %g2, %o0
@@ -81,7 +81,7 @@ __flush_tlb_page:     /* 22 insns */
 
        .align          32
        .globl          __flush_tlb_pending
-__flush_tlb_pending:   /* 26 insns */
+__flush_tlb_pending:   /* 27 insns */
        /* %o0 = context, %o1 = nr, %o2 = vaddrs[] */
        rdpr            %pstate, %g7
        sllx            %o1, 3, %o1
@@ -113,7 +113,7 @@ __flush_tlb_pending:        /* 26 insns */
 
        .align          32
        .globl          __flush_tlb_kernel_range
-__flush_tlb_kernel_range:      /* 16 insns */
+__flush_tlb_kernel_range:      /* 19 insns */
        /* %o0=start, %o1=end */
        cmp             %o0, %o1
        be,pn           %xcc, 2f
@@ -131,6 +131,9 @@ __flush_tlb_kernel_range:   /* 16 insns */
        retl
         nop
        nop
+       nop
+       nop
+       nop
 
 __spitfire_flush_tlb_mm_slow:
        rdpr            %pstate, %g1
@@ -309,19 +312,28 @@ __hypervisor_tlb_tl0_error:
        ret
         restore
 
-__hypervisor_flush_tlb_mm: /* 10 insns */
+__hypervisor_flush_tlb_mm: /* 19 insns */
        mov             %o0, %o2        /* ARG2: mmu context */
        mov             0, %o0          /* ARG0: CPU lists unimplemented */
        mov             0, %o1          /* ARG1: CPU lists unimplemented */
        mov             HV_MMU_ALL, %o3 /* ARG3: flags */
        mov             HV_FAST_MMU_DEMAP_CTX, %o5
        ta              HV_FAST_TRAP
-       brnz,pn         %o0, __hypervisor_tlb_tl0_error
+       brnz,pn         %o0, 1f
         mov            HV_FAST_MMU_DEMAP_CTX, %o1
        retl
         nop
+1:     sethi           %hi(__hypervisor_tlb_tl0_error), %o5
+       jmpl            %o5 + %lo(__hypervisor_tlb_tl0_error), %g0
+        nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
 
-__hypervisor_flush_tlb_page: /* 11 insns */
+__hypervisor_flush_tlb_page: /* 22 insns */
        /* %o0 = context, %o1 = vaddr */
        mov             %o0, %g2
        mov             %o1, %o0              /* ARG0: vaddr + IMMU-bit */
@@ -330,10 +342,21 @@ __hypervisor_flush_tlb_page: /* 11 insns */
        srlx            %o0, PAGE_SHIFT, %o0
        sllx            %o0, PAGE_SHIFT, %o0
        ta              HV_MMU_UNMAP_ADDR_TRAP
-       brnz,pn         %o0, __hypervisor_tlb_tl0_error
+       brnz,pn         %o0, 1f
         mov            HV_MMU_UNMAP_ADDR_TRAP, %o1
        retl
         nop
+1:     sethi           %hi(__hypervisor_tlb_tl0_error), %o2
+       jmpl            %o2 + %lo(__hypervisor_tlb_tl0_error), %g0
+        nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
 
 __hypervisor_flush_tlb_pending: /* 16 insns */
        /* %o0 = context, %o1 = nr, %o2 = vaddrs[] */
@@ -347,14 +370,25 @@ __hypervisor_flush_tlb_pending: /* 16 insns */
        srlx            %o0, PAGE_SHIFT, %o0
        sllx            %o0, PAGE_SHIFT, %o0
        ta              HV_MMU_UNMAP_ADDR_TRAP
-       brnz,pn         %o0, __hypervisor_tlb_tl0_error
+       brnz,pn         %o0, 1f
         mov            HV_MMU_UNMAP_ADDR_TRAP, %o1
        brnz,pt         %g1, 1b
         nop
        retl
         nop
+1:     sethi           %hi(__hypervisor_tlb_tl0_error), %o2
+       jmpl            %o2 + %lo(__hypervisor_tlb_tl0_error), %g0
+        nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
+       nop
 
-__hypervisor_flush_tlb_kernel_range: /* 16 insns */
+__hypervisor_flush_tlb_kernel_range: /* 19 insns */
        /* %o0=start, %o1=end */
        cmp             %o0, %o1
        be,pn           %xcc, 2f
@@ -366,12 +400,15 @@ __hypervisor_flush_tlb_kernel_range: /* 16 insns */
        mov             0, %o1          /* ARG1: mmu context */
        mov             HV_MMU_ALL, %o2 /* ARG2: flags */
        ta              HV_MMU_UNMAP_ADDR_TRAP
-       brnz,pn         %o0, __hypervisor_tlb_tl0_error
+       brnz,pn         %o0, 3f
         mov            HV_MMU_UNMAP_ADDR_TRAP, %o1
        brnz,pt         %g2, 1b
         sub            %g2, %g3, %g2
 2:     retl
         nop
+3:     sethi           %hi(__hypervisor_tlb_tl0_error), %o2
+       jmpl            %o2 + %lo(__hypervisor_tlb_tl0_error), %g0
+        nop
 
 #ifdef DCACHE_ALIASING_POSSIBLE
        /* XXX Niagara and friends have an 8K cache, so no aliasing is
@@ -819,28 +856,28 @@ hypervisor_patch_cachetlbops:
        sethi           %hi(__hypervisor_flush_tlb_mm), %o1
        or              %o1, %lo(__hypervisor_flush_tlb_mm), %o1
        call            tlb_patch_one
-        mov            10, %o2
+        mov            19, %o2
 
        sethi           %hi(__flush_tlb_page), %o0
        or              %o0, %lo(__flush_tlb_page), %o0
        sethi           %hi(__hypervisor_flush_tlb_page), %o1
        or              %o1, %lo(__hypervisor_flush_tlb_page), %o1
        call            tlb_patch_one
-        mov            11, %o2
+        mov            22, %o2
 
        sethi           %hi(__flush_tlb_pending), %o0
        or              %o0, %lo(__flush_tlb_pending), %o0
        sethi           %hi(__hypervisor_flush_tlb_pending), %o1
        or              %o1, %lo(__hypervisor_flush_tlb_pending), %o1
        call            tlb_patch_one
-        mov            16, %o2
+        mov            27, %o2
 
        sethi           %hi(__flush_tlb_kernel_range), %o0
        or              %o0, %lo(__flush_tlb_kernel_range), %o0
        sethi           %hi(__hypervisor_flush_tlb_kernel_range), %o1
        or              %o1, %lo(__hypervisor_flush_tlb_kernel_range), %o1
        call            tlb_patch_one
-        mov            16, %o2
+        mov            19, %o2
 
 #ifdef DCACHE_ALIASING_POSSIBLE
        sethi           %hi(__flush_dcache_page), %o0