[PATCH v2 1/3] selftests/powerpc: Allocate base registers

[Breno Leitao]

Some ptrace selftests are passing input operands using a constraint that
can allocate any register for the operand, and using these registers on
load/store operations.

If the register allocated by the compiler happens to be zero (r0), it might
cause an invalid memory address access, since load and store operations
consider the content of 0x0 address if the base register is r0, instead of
the content of the r0 register. For example:

	r1 := 0xdeadbeef
	r0 := 0xdeadbeef

	ld r2, 0(1) /* will load into r2 the content of r1 address */
	ld r2, 0(0) /* will load into r2 the content of 0x0 */

In order to avoid this possible problem, the inline assembly constraint
should be aware that these registers will be used as a base register, thus,
r0 should not be allocated.

Other than that, this patch removes inline assembly operands that are not
used by the tests.

Signed-off-by: Breno Leitao <leitao at debian.org>
Reviewed-by: Segher Boessenkool <segher at kernel.crashing.org>
---
 tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c        | 2 +-
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c     | 4 ++--
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c | 2 +-
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c | 3 +--
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c     | 2 +-
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c     | 2 +-
 tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c     | 3 +--
 7 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c b/tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c
index 0b4ebcc2f485..ca29fafeed5d 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-gpr.c
@@ -31,7 +31,7 @@ void gpr(void)
 		ASM_LOAD_GPR_IMMED(gpr_1)
 		ASM_LOAD_FPR_SINGLE_PRECISION(flt_1)
 		:
-		: [gpr_1]"i"(GPR_1), [flt_1] "r" (&a)
+		: [gpr_1]"i"(GPR_1), [flt_1] "b" (&a)
 		: "memory", "r6", "r7", "r8", "r9", "r10",
 		"r11", "r12", "r13", "r14", "r15", "r16", "r17",
 		"r18", "r19", "r20", "r21", "r22", "r23", "r24",
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c
index 59206b96e98a..a08a91594dbe 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c
@@ -59,8 +59,8 @@ void tm_gpr(void)
 		"3: ;"
 		: [res] "=r" (result), [texasr] "=r" (texasr)
 		: [gpr_1]"i"(GPR_1), [gpr_2]"i"(GPR_2),
-		[sprn_texasr] "i" (SPRN_TEXASR), [flt_1] "r" (&a),
-		[flt_2] "r" (&b), [cptr1] "r" (&cptr[1])
+		[sprn_texasr] "i" (SPRN_TEXASR), [flt_1] "b" (&a),
+		[flt_2] "b" (&b), [cptr1] "b" (&cptr[1])
 		: "memory", "r7", "r8", "r9", "r10",
 		"r11", "r12", "r13", "r14", "r15", "r16",
 		"r17", "r18", "r19", "r20", "r21", "r22",
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c
index b3c061dc9512..f47174746231 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c
@@ -72,7 +72,7 @@ void tm_spd_tar(void)
 		"3: ;"
 
 		: [res] "=r" (result), [texasr] "=r" (texasr)
-		: [val] "r" (cptr[1]), [sprn_dscr]"i"(SPRN_DSCR),
+		: [sprn_dscr]"i"(SPRN_DSCR),
 		[sprn_tar]"i"(SPRN_TAR), [sprn_ppr]"i"(SPRN_PPR),
 		[sprn_texasr]"i"(SPRN_TEXASR), [tar_1]"i"(TAR_1),
 		[dscr_1]"i"(DSCR_1), [tar_2]"i"(TAR_2), [dscr_2]"i"(DSCR_2),
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c
index 277dade1b382..18a685bf6a09 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c
@@ -77,8 +77,7 @@ void tm_spd_vsx(void)
 
 		"3: ;"
 		: [res] "=r" (result), [texasr] "=r" (texasr)
-		: [fp_load] "r" (fp_load), [fp_load_ckpt] "r" (fp_load_ckpt),
-		[sprn_texasr] "i"  (SPRN_TEXASR)
+		: [sprn_texasr] "i"  (SPRN_TEXASR)
 		: "memory", "r0", "r1", "r3", "r4",
 		"r7", "r8", "r9", "r10", "r11"
 		);
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c
index 51427a2465f6..ba04999254e3 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c
@@ -74,7 +74,7 @@ void tm_spr(void)
 
 		"3: ;"
 		: [tfhar] "=r" (tfhar), [res] "=r" (result),
-		[texasr] "=r" (texasr), [cptr1] "=r" (cptr1)
+		[texasr] "=r" (texasr), [cptr1] "=b" (cptr1)
 		: [sprn_texasr] "i"  (SPRN_TEXASR)
 		: "memory", "r0", "r8", "r31"
 		);
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c
index 48b462f75023..f70023b25e6e 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c
@@ -65,7 +65,7 @@ void tm_tar(void)
 		: [sprn_dscr]"i"(SPRN_DSCR), [sprn_tar]"i"(SPRN_TAR),
 		[sprn_ppr]"i"(SPRN_PPR), [sprn_texasr]"i"(SPRN_TEXASR),
 		[tar_1]"i"(TAR_1), [dscr_1]"i"(DSCR_1), [tar_2]"i"(TAR_2),
-		[dscr_2]"i"(DSCR_2), [cptr1] "r" (&cptr[1])
+		[dscr_2]"i"(DSCR_2), [cptr1] "b" (&cptr[1])
 		: "memory", "r0", "r1", "r3", "r4", "r5", "r6"
 		);
 
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c
index 17c23cabac3e..dfba80058977 100644
--- a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c
@@ -65,8 +65,7 @@ void tm_vsx(void)
 
 		"3: ;"
 		: [res] "=r" (result), [texasr] "=r" (texasr)
-		: [fp_load] "r" (fp_load), [fp_load_ckpt] "r" (fp_load_ckpt),
-		[sprn_texasr] "i"  (SPRN_TEXASR), [cptr1] "r" (&cptr[1])
+		: [sprn_texasr] "i"  (SPRN_TEXASR), [cptr1] "b" (&cptr[1])
 		: "memory", "r0", "r1", "r3", "r4",
 		"r7", "r8", "r9", "r10", "r11"
 		);
-- 
2.13.2