From 22d6b013ffcf4809b4fe03b240855c6f8eb54599 Mon Sep 17 00:00:00 2001 From: Dave Aldridge Date: Tue, 9 May 2017 02:57:35 -0600 Subject: sparc64: fix fault handling in NGbzero.S and GENbzero.S 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(-) (limited to 'arch/sparc') diff --git a/arch/sparc/kernel/head_64.S b/arch/sparc/kernel/head_64.S index 6aa3da152c20..9835152a0682 100644 --- a/arch/sparc/kernel/head_64.S +++ b/arch/sparc/kernel/head_64.S @@ -935,3 +935,9 @@ 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) diff --git a/arch/sparc/lib/GENbzero.S b/arch/sparc/lib/GENbzero.S index 8e7a843ddd88..2fbf6297d57c 100644 --- 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; diff --git a/arch/sparc/lib/NGbzero.S b/arch/sparc/lib/NGbzero.S index beab29bf419b..33053bdf3766 100644 --- 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; -- cgit v1.2.3