diff options
Diffstat (limited to 'target/linux/patches/4.19.151/0001-Revert-ARC-entry-fix-potential-EFA-clobber-when-TIF_.patch')
| -rw-r--r-- | target/linux/patches/4.19.151/0001-Revert-ARC-entry-fix-potential-EFA-clobber-when-TIF_.patch | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/target/linux/patches/4.19.151/0001-Revert-ARC-entry-fix-potential-EFA-clobber-when-TIF_.patch b/target/linux/patches/4.19.151/0001-Revert-ARC-entry-fix-potential-EFA-clobber-when-TIF_.patch new file mode 100644 index 000000000..1215bb6d0 --- /dev/null +++ b/target/linux/patches/4.19.151/0001-Revert-ARC-entry-fix-potential-EFA-clobber-when-TIF_.patch @@ -0,0 +1,66 @@ +From af5e43cd88d4b7d59260de6bdacbf715e2a7ff5d Mon Sep 17 00:00:00 2001 +From: Waldemar Brodkorb <wbx@openadk.org> +Date: Fri, 16 Oct 2020 01:17:24 +0200 +Subject: [PATCH] Revert "ARC: entry: fix potential EFA clobber when + TIF_SYSCALL_TRACE" + +This reverts commit 01b636cbc4c39c7073c02c2f1dfbe8c36c11938f. + +Signed-off-by: Waldemar Brodkorb <wbx@openadk.org> +--- + arch/arc/kernel/entry.S | 16 +++++++++++----- + 1 file changed, 11 insertions(+), 5 deletions(-) + +diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S +index 705a68208423..85d9ea4a0acc 100644 +--- a/arch/arc/kernel/entry.S ++++ b/arch/arc/kernel/entry.S +@@ -156,6 +156,7 @@ END(EV_Extension) + tracesys: + ; save EFA in case tracer wants the PC of traced task + ; using ERET won't work since next-PC has already committed ++ lr r12, [efa] + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11 + st r12, [r11, THREAD_FAULT_ADDR] ; thread.fault_address + +@@ -198,9 +199,15 @@ tracesys_exit: + ; Breakpoint TRAP + ; --------------------------------------------- + trap_with_param: +- mov r0, r12 ; EFA in case ptracer/gdb wants stop_pc ++ ++ ; stop_pc info by gdb needs this info ++ lr r0, [efa] + mov r1, sp + ++ ; Now that we have read EFA, it is safe to do "fake" rtie ++ ; and get out of CPU exception mode ++ FAKE_RET_FROM_EXCPN ++ + ; Save callee regs in case gdb wants to have a look + ; SP will grow up by size of CALLEE Reg-File + ; NOTE: clobbers r12 +@@ -227,10 +234,6 @@ ENTRY(EV_Trap) + + EXCEPTION_PROLOGUE + +- lr r12, [efa] +- +- FAKE_RET_FROM_EXCPN +- + ;============ TRAP 1 :breakpoints + ; Check ECR for trap with arg (PROLOGUE ensures r9 has ECR) + bmsk.f 0, r9, 7 +@@ -238,6 +241,9 @@ ENTRY(EV_Trap) + + ;============ TRAP (no param): syscall top level + ++ ; First return from Exception to pure K mode (Exception/IRQs renabled) ++ FAKE_RET_FROM_EXCPN ++ + ; If syscall tracing ongoing, invoke pre-post-hooks + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE +-- +2.11.0 + |