From 6a0e8bb4956c34328f4624e20bd3a6c2b1d90adc Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Sun, 31 May 2020 13:02:31 +0200 Subject: target/m68k: implement fmove.l #,FPCR The immediate value mode was ignored and instruction execution ends to an invalid access mode. This was found running 'R' that set FPSR to 0 at startup with a 'fmove.l #0,FPSR' in qemu-system-m68k emulation and triggers a kernel crash: [ 56.640000] *** ADDRESS ERROR *** FORMAT=2 [ 56.640000] Current process id is 728 [ 56.640000] BAD KERNEL TRAP: 00000000 [ 56.640000] Modules linked in: sg evdev mac_hid ip_tables x_tables sha1_generic hmac ipv6 nf_defrag_ipv6 autofs4 ext4 crc16 mbcache jbd2 crc32c_generic sd_mod t10_pi crc_t10dif crct10dif_generic crct10dif_common sr_mod cdrom mac_esp macsonic esp_scsi [ 56.640000] PC: [<00016a2c>] X_UNSUPP+0x2c/0x3c [ 56.640000] SR: 2004 SP: 3eb5e68c a2: c02e239a [ 56.640000] d0: 00000040 d1: 00000002 d2: 8002adec d3: 8002ad50 [ 56.640000] d4: 8002c768 d5: 0000000d a0: ffffffc2 a1: ffffffc1 [ 56.640000] Process R (pid: 728, task=a3dfda5d) [ 56.640000] Frame format=2 instr addr=00000000 [ 56.650000] Stack from 3a4d9f30: [ 56.650000] 41000000 00000002 00000002 ffffffc2 ffffffc1 1fff0000 80000000 00000000 [ 56.650000] 3fbf0000 80000000 00000000 00000000 20000000 00000000 7fff0000 ffffffff [ 56.650000] ffffffff 00000000 00050008 00000000 8000067c c02c2000 efffee20 000002d8 [ 56.650000] 00002a28 3a4d9f98 00000002 00000014 fffffffe 8002c768 00000002 00000041 [ 56.650000] 00000002 c041fc58 c0743758 ffffffff 00000000 0008c075 00002b24 00000012 [ 56.650000] 000007d0 00000024 00000002 c05bef04 c05bef04 0000005e 00000077 c28aca70 [ 56.650000] Call Trace: [<00050008>] copy_overflow+0x10/0x28 [ 56.650000] [<00002a28>] buserr+0x20/0x28 [ 56.650000] [<0008c075>] bpf_check+0x57f/0x1cfa [ 56.650000] [<00002b24>] syscall+0x8/0xc [ 56.650000] [<0000c019>] dn_sched_init+0x75/0x88 [ 56.650000] Code: 1017 0200 00f0 0c00 0040 66ff 0000 05ac 8800 0000 0000 f23c 9000 0000 0000 222e ff84 082e 0005 ff1c 6600 000a 0281 [ 56.650000] Disabling lock debugging due to kernel taint ... Reported-by: John Paul Adrian Glaubitz Signed-off-by: Laurent Vivier Tested-by: John Paul Adrian Glaubitz Reviewed-by: Richard Henderson Message-Id: <20200531110231.620711-1-laurent@vivier.eu> Signed-off-by: Laurent Vivier --- target/m68k/translate.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'target/m68k') diff --git a/target/m68k/translate.c b/target/m68k/translate.c index 0f80888203..c093f6c683 100644 --- a/target/m68k/translate.c +++ b/target/m68k/translate.c @@ -4936,6 +4936,20 @@ static void gen_op_fmove_fcr(CPUM68KState *env, DisasContext *s, gen_store_fcr(s, AREG(insn, 0), mask); } return; + case 7: /* Immediate */ + if (REG(insn, 0) == 4) { + if (is_write || + (mask != M68K_FPIAR && mask != M68K_FPSR && + mask != M68K_FPCR)) { + gen_exception(s, s->base.pc_next, EXCP_ILLEGAL); + return; + } + tmp = tcg_const_i32(read_im32(env, s)); + gen_store_fcr(s, tmp, mask); + tcg_temp_free(tmp); + return; + } + break; default: break; } -- cgit v1.2.3