diff options
| author | nwhitehorn <nwhitehorn@FreeBSD.org> | 2012-04-11 00:00:40 +0000 |
|---|---|---|
| committer | nwhitehorn <nwhitehorn@FreeBSD.org> | 2012-04-11 00:00:40 +0000 |
| commit | 5ff92b1d9cf05d81d6ba6e43fbac5f0e1005df63 (patch) | |
| tree | fa4399d543adb338238e40a89c2c950e43bc75b5 /sys/powerpc/powerpc | |
| parent | f0d73b67412f77f8ec067ccb7e25190dce1a3a14 (diff) | |
| download | FreeBSD-src-5ff92b1d9cf05d81d6ba6e43fbac5f0e1005df63.zip FreeBSD-src-5ff92b1d9cf05d81d6ba6e43fbac5f0e1005df63.tar.gz | |
Do not restore the register holding the TLS pointer when doing various
usermode context switches (long jumps and ucontext operations). If these
are used across threads, multiple threads can end up with the same TLS base.
Madness will then result.
This makes behavior on PPC match that on x86 systems and on Linux.
MFC after: 10 days
Diffstat (limited to 'sys/powerpc/powerpc')
| -rw-r--r-- | sys/powerpc/powerpc/exec_machdep.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/sys/powerpc/powerpc/exec_machdep.c b/sys/powerpc/powerpc/exec_machdep.c index ec88d9f..a23fd4c 100644 --- a/sys/powerpc/powerpc/exec_machdep.c +++ b/sys/powerpc/powerpc/exec_machdep.c @@ -441,6 +441,7 @@ set_mcontext(struct thread *td, const mcontext_t *mcp) { struct pcb *pcb; struct trapframe *tf; + register_t tls; pcb = td->td_pcb; tf = td->td_frame; @@ -448,16 +449,25 @@ set_mcontext(struct thread *td, const mcontext_t *mcp) if (mcp->mc_vers != _MC_VERSION || mcp->mc_len != sizeof(*mcp)) return (EINVAL); - #ifdef AIM +#ifdef AIM /* * Don't let the user set privileged MSR bits */ if ((mcp->mc_srr1 & PSL_USERSTATIC) != (tf->srr1 & PSL_USERSTATIC)) { return (EINVAL); } - #endif +#endif + /* Copy trapframe, preserving TLS pointer across context change */ + if (SV_PROC_FLAG(td->td_proc, SV_LP64)) + tls = tf->fixreg[13]; + else + tls = tf->fixreg[2]; memcpy(tf, mcp->mc_frame, sizeof(mcp->mc_frame)); + if (SV_PROC_FLAG(td->td_proc, SV_LP64)) + tf->fixreg[13] = tls; + else + tf->fixreg[2] = tls; #ifdef AIM if (mcp->mc_flags & _MC_FP_VALID) { |
