[Lldb-commits] [lldb] 257aa19 - [lldb][FreeBSDKernel] Supply values for CS/SS registers (#192207)

[via lldb-commits]

Author: Minsoo Choo
Date: 2026-04-15T17:51:49+09:00
New Revision: 257aa195199cb10e5f4559399f91bbb6713ea93b

URL: https://github.com/llvm/llvm-project/commit/257aa195199cb10e5f4559399f91bbb6713ea93b
DIFF: https://github.com/llvm/llvm-project/commit/257aa195199cb10e5f4559399f91bbb6713ea93b.diff

LOG: [lldb][FreeBSDKernel] Supply values for CS/SS registers (#192207)

These two values ensure that CPU was in kernel privilege at the time of
crash. This change is from KGDB's `amd64fbsd-kern.c`.

Signed-off-by: Minsoo Choo <minsoochoo0122 at proton.me>

Added: 
    

Modified: 
    lldb/source/Plugins/Process/FreeBSD-Kernel-Core/RegisterContextFreeBSDKernelCore_x86_64.cpp

Removed: 
    


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diff  --git a/lldb/source/Plugins/Process/FreeBSD-Kernel-Core/RegisterContextFreeBSDKernelCore_x86_64.cpp b/lldb/source/Plugins/Process/FreeBSD-Kernel-Core/RegisterContextFreeBSDKernelCore_x86_64.cpp
index 8f833aa47e486..a0cb53526d331 100644
--- a/lldb/source/Plugins/Process/FreeBSD-Kernel-Core/RegisterContextFreeBSDKernelCore_x86_64.cpp
+++ b/lldb/source/Plugins/Process/FreeBSD-Kernel-Core/RegisterContextFreeBSDKernelCore_x86_64.cpp
@@ -58,6 +58,9 @@ bool RegisterContextFreeBSDKernelCore_x86_64::ReadRegister(
     llvm::support::ulittle64_t rip;
   } pcb;
 
+  constexpr unsigned short CODE_SEL = 4 << 3;
+  constexpr unsigned short DATA_SEL = 5 << 3;
+
 #if defined(__FreeBSD__) && defined(__amd64__)
   static_assert(offsetof(struct pcb, pcb_r15) == offsetof(decltype(pcb), r15));
   static_assert(offsetof(struct pcb, pcb_r14) == offsetof(decltype(pcb), r14));
@@ -90,9 +93,13 @@ bool RegisterContextFreeBSDKernelCore_x86_64::ReadRegister(
     REG(rsp);
     REG(rbx);
     REG(rip);
-
 #undef REG
-
+  case lldb_cs_x86_64:
+    value.SetUInt(CODE_SEL, reg_info->byte_size);
+    break;
+  case lldb_ss_x86_64:
+    value.SetUInt(DATA_SEL, reg_info->byte_size);
+    break;
   default:
     return false;
   }