git: eea3e4dd9703 - main - amd64: add mc_tlsbase member to mcontext

[Konstantin Belousov]

The branch main has been updated by kib:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=eea3e4dd9703a252509d75814049aa8da5007ebb

commit eea3e4dd9703a252509d75814049aa8da5007ebb
Author:     Konstantin Belousov <k...@freebsd.org>
AuthorDate: 2025-05-22 06:55:50 +0000
Commit:     Konstantin Belousov <k...@freebsd.org>
CommitDate: 2025-05-28 11:11:23 +0000

    amd64: add mc_tlsbase member to mcontext
    
    Tested by:      pho
    Reviewed by:    olce
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D50482
---
 sys/amd64/amd64/exec_machdep.c | 6 ++++++
 sys/x86/include/frame.h        | 1 +
 sys/x86/include/ucontext.h     | 8 ++++++--
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/sys/amd64/amd64/exec_machdep.c b/sys/amd64/amd64/exec_machdep.c
index 46e4f0c9e07b..da68289e2c83 100644
--- a/sys/amd64/amd64/exec_machdep.c
+++ b/sys/amd64/amd64/exec_machdep.c
@@ -635,6 +635,8 @@ get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
        mcp->mc_gsbase = pcb->pcb_gsbase;
        mcp->mc_xfpustate = 0;
        mcp->mc_xfpustate_len = 0;
+       mcp->mc_tlsbase = (pcb->pcb_flags & PCB_TLSBASE) != 0 ?
+           pcb->pcb_tlsbase : 0;
        bzero(mcp->mc_spare, sizeof(mcp->mc_spare));
        return (0);
 }
@@ -709,6 +711,10 @@ set_mcontext(struct thread *td, mcontext_t *mcp)
                pcb->pcb_fsbase = mcp->mc_fsbase;
                pcb->pcb_gsbase = mcp->mc_gsbase;
        }
+       if ((mcp->mc_flags & _MC_HASTLSBASE) != 0) {
+               pcb->pcb_tlsbase = mcp->mc_tlsbase;
+               set_pcb_flags(pcb, PCB_TLSBASE);
+       }
        return (0);
 }
 
diff --git a/sys/x86/include/frame.h b/sys/x86/include/frame.h
index 9574e8c0ed02..994e19b979fc 100644
--- a/sys/x86/include/frame.h
+++ b/sys/x86/include/frame.h
@@ -152,6 +152,7 @@ struct trapframe {
 #define        TF_HASSEGS      0x1
 #define        TF_HASBASES     0x2
 #define        TF_HASFPXSTATE  0x4
+#define        TF_RESERV0      0x8 /* no tlsbase in the trapframe */
 #endif /* __amd64__ */
 
 #endif /* _MACHINE_FRAME_H_ */
diff --git a/sys/x86/include/ucontext.h b/sys/x86/include/ucontext.h
index b7964e8c7141..00edc8c16bce 100644
--- a/sys/x86/include/ucontext.h
+++ b/sys/x86/include/ucontext.h
@@ -99,7 +99,9 @@ typedef struct __mcontext {
 #define        _MC_HASSEGS     0x1
 #define        _MC_HASBASES    0x2
 #define        _MC_HASFPXSTATE 0x4
-#define        _MC_FLAG_MASK   (_MC_HASSEGS | _MC_HASBASES | _MC_HASFPXSTATE)
+#define        _MC_HASTLSBASE  0x8
+#define        _MC_FLAG_MASK   (_MC_HASSEGS | _MC_HASBASES | _MC_HASFPXSTATE | 
\
+    _MC_HASTLSBASE)
 
 typedef struct __mcontext {
        /*
@@ -158,7 +160,9 @@ typedef struct __mcontext {
        __register_t    mc_xfpustate;
        __register_t    mc_xfpustate_len;
 
-       long    mc_spare[4];
+       __register_t    mc_tlsbase;
+
+       long    mc_spare[3];
 } mcontext_t;
 #endif /* __amd64__ */