From fc6cda2ee85d2c2719db3b5ae3a1ae963f28416b Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Fri, 16 Sep 2016 14:58:31 +0100 Subject: [PATCH] Keep reserved bits in CPSR on write In patch https://sourceware.org/ml/gdb-patches/2016-04/msg00529.html I cleared reserved bits when reading CPSR. It makes a problem that these bits (zero) are written back to kernel through ptrace, and it changes the state of the processor on some recent kernel, which is unexpected. In this patch, I keep these reserved bits when write CPSR back to hardware. gdb: 2016-09-21 Yao Qi * aarch32-linux-nat.c (aarch32_gp_regcache_collect): Keep bits 20 to 23. gdb/gdbserver: 2016-09-21 Yao Qi * linux-aarch32-low.c (arm_fill_gregset): Keep bits 20 to 23. --- gdb/ChangeLog | 5 +++++ gdb/aarch32-linux-nat.c | 11 +++++++++-- gdb/gdbserver/ChangeLog | 5 +++++ gdb/gdbserver/linux-aarch32-low.c | 4 ++++ 4 files changed, 23 insertions(+), 2 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index ef18a19..b7b9e54 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2016-09-21 Yao Qi + + * aarch32-linux-nat.c (aarch32_gp_regcache_collect): Keep + bits 20 to 23. + 2016-09-20 Tom Tromey * python/py-value.c (convert_value_from_python): Make PyInt_Check diff --git a/gdb/aarch32-linux-nat.c b/gdb/aarch32-linux-nat.c index 72bf644..2df672d 100644 --- a/gdb/aarch32-linux-nat.c +++ b/gdb/aarch32-linux-nat.c @@ -67,8 +67,15 @@ aarch32_gp_regcache_collect (const struct regcache *regcache, uint32_t *regs, if (arm_apcs_32 && REG_VALID == regcache_register_status (regcache, ARM_PS_REGNUM)) - regcache_raw_collect (regcache, ARM_PS_REGNUM, - ®s[ARM_CPSR_GREGNUM]); + { + uint32_t cpsr = regs[ARM_CPSR_GREGNUM]; + + regcache_raw_collect (regcache, ARM_PS_REGNUM, + ®s[ARM_CPSR_GREGNUM]); + /* Keep reserved bits bit 20 to bit 23. */ + regs[ARM_CPSR_GREGNUM] = ((regs[ARM_CPSR_GREGNUM] & 0xff0fffff) + | (cpsr & 0x00f00000)); + } } /* Supply VFP registers contents, stored in REGS, to REGCACHE. diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index c97c777..c1f1dff 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,8 @@ +2016-09-21 Yao Qi + + * linux-aarch32-low.c (arm_fill_gregset): Keep bits 20 to + 23. + 2016-09-19 Sergio Durigan Junior * server.c (start_inferior): Call target_mourn_inferior instead of diff --git a/gdb/gdbserver/linux-aarch32-low.c b/gdb/gdbserver/linux-aarch32-low.c index e6971d5..463bce6 100644 --- a/gdb/gdbserver/linux-aarch32-low.c +++ b/gdb/gdbserver/linux-aarch32-low.c @@ -62,11 +62,15 @@ arm_fill_gregset (struct regcache *regcache, void *buf) { int i; uint32_t *regs = (uint32_t *) buf; + uint32_t cpsr = regs[ARM_CPSR_GREGNUM]; for (i = ARM_A1_REGNUM; i <= ARM_PC_REGNUM; i++) collect_register (regcache, i, ®s[i]); collect_register (regcache, ARM_PS_REGNUM, ®s[ARM_CPSR_GREGNUM]); + /* Keep reserved bits bit 20 to bit 23. */ + regs[ARM_CPSR_GREGNUM] = ((regs[ARM_CPSR_GREGNUM] & 0xff0fffff) + | (cpsr & 0x00f00000)); } /* Supply GP registers contents, stored in BUF, to REGCACHE. */ -- 2.7.4