[PATCH 4.11 06/28] sparc64: fix fault handling in NGbzero.S and GENbzero.S
4.11-stable review patch. If anyone has any objections, please let me know. -- From: Dave Aldridgecommit 3c7f62212018b904ae17f5636ead18a4dca3a88f upstream. When any of the functions contained in NGbzero.S and GENbzero.S vector through *bzero_from_clear_user, we may end up taking a fault when executing one of the store alternate address space instructions. If this happens, the exception handler does not restore the %asi register. This commit fixes the issue by introducing a new exception handler that ensures the %asi register is restored when a fault is handled. Orabug: 25577560 Signed-off-by: Dave Aldridge Reviewed-by: Rob Gardner Reviewed-by: Babu Moger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- arch/sparc/kernel/head_64.S |6 ++ arch/sparc/lib/GENbzero.S |2 +- arch/sparc/lib/NGbzero.S|2 +- 3 files changed, 8 insertions(+), 2 deletions(-) --- a/arch/sparc/kernel/head_64.S +++ b/arch/sparc/kernel/head_64.S @@ -939,3 +939,9 @@ ENTRY(__retl_o1) retl mov%o1, %o0 ENDPROC(__retl_o1) + +ENTRY(__retl_o1_asi) + wr %o5, 0x0, %asi + retl +mov%o1, %o0 +ENDPROC(__retl_o1_asi) --- a/arch/sparc/lib/GENbzero.S +++ b/arch/sparc/lib/GENbzero.S @@ -8,7 +8,7 @@ 98:x,y;\ .section __ex_table,"a";\ .align 4; \ - .word 98b, __retl_o1; \ + .word 98b, __retl_o1_asi;\ .text; \ .align 4; --- a/arch/sparc/lib/NGbzero.S +++ b/arch/sparc/lib/NGbzero.S @@ -8,7 +8,7 @@ 98:x,y;\ .section __ex_table,"a";\ .align 4; \ - .word 98b, __retl_o1; \ + .word 98b, __retl_o1_asi;\ .text; \ .align 4;
[PATCH 4.11 06/28] sparc64: fix fault handling in NGbzero.S and GENbzero.S
4.11-stable review patch. If anyone has any objections, please let me know. -- From: Dave Aldridge commit 3c7f62212018b904ae17f5636ead18a4dca3a88f upstream. When any of the functions contained in NGbzero.S and GENbzero.S vector through *bzero_from_clear_user, we may end up taking a fault when executing one of the store alternate address space instructions. If this happens, the exception handler does not restore the %asi register. This commit fixes the issue by introducing a new exception handler that ensures the %asi register is restored when a fault is handled. Orabug: 25577560 Signed-off-by: Dave Aldridge Reviewed-by: Rob Gardner Reviewed-by: Babu Moger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- arch/sparc/kernel/head_64.S |6 ++ arch/sparc/lib/GENbzero.S |2 +- arch/sparc/lib/NGbzero.S|2 +- 3 files changed, 8 insertions(+), 2 deletions(-) --- a/arch/sparc/kernel/head_64.S +++ b/arch/sparc/kernel/head_64.S @@ -939,3 +939,9 @@ ENTRY(__retl_o1) retl mov%o1, %o0 ENDPROC(__retl_o1) + +ENTRY(__retl_o1_asi) + wr %o5, 0x0, %asi + retl +mov%o1, %o0 +ENDPROC(__retl_o1_asi) --- a/arch/sparc/lib/GENbzero.S +++ b/arch/sparc/lib/GENbzero.S @@ -8,7 +8,7 @@ 98:x,y;\ .section __ex_table,"a";\ .align 4; \ - .word 98b, __retl_o1; \ + .word 98b, __retl_o1_asi;\ .text; \ .align 4; --- a/arch/sparc/lib/NGbzero.S +++ b/arch/sparc/lib/NGbzero.S @@ -8,7 +8,7 @@ 98:x,y;\ .section __ex_table,"a";\ .align 4; \ - .word 98b, __retl_o1; \ + .word 98b, __retl_o1_asi;\ .text; \ .align 4;