| Message ID | 20220223135820.2252470-3-anders.roxell@linaro.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [1/3] powerpc: lib: sstep: fix 'sthcx' instruction | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 7 jobs. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | fail | boot (ppc64le_guest_defconfig, pseries+p8+tcg, pseries+p9+tcg, qemu-system-ppc64, ppc64le-rootfs.... failed at step Run qemu-pseries+p8+tcg with korg-5.5.0 build kernel. |
On Wed, Feb 23, 2022 at 02:58:20PM +0100, Anders Roxell wrote: > Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian > 2.37.90.20220207) the following build error shows up: > > {standard input}: Assembler messages: > {standard input}:10576: Error: unrecognized opcode: `stbcx.' > {standard input}:10680: Error: unrecognized opcode: `lharx' > {standard input}:10694: Error: unrecognized opcode: `lbarx' > > Rework to add assembler directives [1] around the instruction. The > problem with this might be that we can trick a power6 into > single-stepping through an stbcx. for instance, and it will execute that > in kernel mode. > > [1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo Wow, no wonder you think you need quotes after reading that. I'll try to get that fixed. Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Segher
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index d2d29243fa6d..b9f43bbdd55a 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -1097,7 +1097,10 @@ NOKPROBE_SYMBOL(emulate_dcbz); #define __put_user_asmx(x, addr, err, op, cr) \ __asm__ __volatile__( \ + ".machine \"push\"\n" \ + ".machine \"power8\"\n" \ "1: " op " %2,0,%3\n" \ + ".machine \"pop\"\n" \ " mfcr %1\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ @@ -1110,7 +1113,10 @@ NOKPROBE_SYMBOL(emulate_dcbz); #define __get_user_asmx(x, addr, err, op) \ __asm__ __volatile__( \ + ".machine \"push\"\n" \ + ".machine \"power8\"\n" \ "1: "op" %1,0,%2\n" \ + ".machine \"pop\"\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3: li %0,%3\n" \
Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian 2.37.90.20220207) the following build error shows up: {standard input}: Assembler messages: {standard input}:10576: Error: unrecognized opcode: `stbcx.' {standard input}:10680: Error: unrecognized opcode: `lharx' {standard input}:10694: Error: unrecognized opcode: `lbarx' Rework to add assembler directives [1] around the instruction. The problem with this might be that we can trick a power6 into single-stepping through an stbcx. for instance, and it will execute that in kernel mode. [1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo Cc: <stable@vger.kernel.org> Co-developed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> --- arch/powerpc/lib/sstep.c | 6 ++++++ 1 file changed, 6 insertions(+)