5.15-stable review patch. If anyone has any objections, please let me know.
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From: Clément Léger cleger@rivosinc.com
[ Upstream commit 22e0eb04837a63af111fae35a92f7577676b9bc8 ]
This is a backport of a fix that was done in OpenSBI: ec0559eb315b ("lib: sbi_misaligned_ldst: Fix handling of C.SWSP and C.SDSP").
Unlike C.LWSP/C.LDSP, these encodings can be used with the zero register, so checking that the rs2 field is non-zero is unnecessary.
Additionally, the previous check was incorrect since it was checking the immediate field of the instruction instead of the rs2 field.
Fixes: 956d705dd279 ("riscv: Unaligned load/store handling for M_MODE") Signed-off-by: Clément Léger cleger@rivosinc.com Link: https://lore.kernel.org/r/20231103090223.702340-1-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/traps_misaligned.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c index 46c4dafe3ba0e..b246c3dc69930 100644 --- a/arch/riscv/kernel/traps_misaligned.c +++ b/arch/riscv/kernel/traps_misaligned.c @@ -344,16 +344,14 @@ int handle_misaligned_store(struct pt_regs *regs) } else if ((insn & INSN_MASK_C_SD) == INSN_MATCH_C_SD) { len = 8; val.data_ulong = GET_RS2S(insn, regs); - } else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP && - ((insn >> SH_RD) & 0x1f)) { + } else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP) { len = 8; val.data_ulong = GET_RS2C(insn, regs); #endif } else if ((insn & INSN_MASK_C_SW) == INSN_MATCH_C_SW) { len = 4; val.data_ulong = GET_RS2S(insn, regs); - } else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP && - ((insn >> SH_RD) & 0x1f)) { + } else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP) { len = 4; val.data_ulong = GET_RS2C(insn, regs); } else {