gdb/gdb-rhbz1870029-powerpc-remove-region-limit-dawr.patch
Keith Seitz 4748efc8fa Backport "PowerPC remove 512 bytes region limit if 2nd DAWR is available"
(Rogerio Alves, RHBZ 1870029)
Backport patches for "Support prefixed instructions in GDB"
(Will Schmidt and Luis Machado, RHBZ 1870031)

Resolves: rhbz#1870029
Resolves: rhbz#1870031
2021-06-28 18:37:39 -04:00

80 lines
3.2 KiB
Diff

From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Keith Seitz <keiths@redhat.com>
Date: Wed, 5 May 2021 09:11:12 -0700
Subject: gdb-rhbz1870029-powerpc-remove-region-limit-dawr.patch
;; Backport "PowerPC remove 512 bytes region limit if 2nd DAWR is available"
;; (Rogerio Alves, RHBZ 1870029)
commit 539d71e89a21990d9fd15641477e4790129bdb11
Author: Rogerio Alves <rcardoso@linux.ibm.com>
Date: Tue Dec 1 16:53:38 2020 -0300
PowerPC remove 512 bytes region limit if 2nd DAWR is avaliable.
Power 10 introduces the 2nd DAWR (second watchpoint) and also removed
a restriction that limit the watch region to 512 bytes.
2020-11-08 Rogerio A. Cardoso <rcardoso@linux.ibm.com>
/gdb
* ppc-linux-nat.c: (PPC_DEBUG_FEATURE_DATA_BP_ARCH_31): New define.
(region_ok_for_hw_watchpoint): Check if 2nd DAWR is avaliable before
set region.
diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c
--- a/gdb/ppc-linux-nat.c
+++ b/gdb/ppc-linux-nat.c
@@ -138,6 +138,11 @@ struct ppc_hw_breakpoint
#define PPC_DEBUG_FEATURE_DATA_BP_DAWR 0x10
#endif /* PPC_DEBUG_FEATURE_DATA_BP_DAWR */
+/* Feature defined on Linux kernel v5.1: Second watchpoint support. */
+#ifndef PPC_DEBUG_FEATURE_DATA_BP_ARCH_31
+#define PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 0x20
+#endif /* PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 */
+
/* The version of the PowerPC HWDEBUG kernel interface that we will use, if
available. */
#define PPC_DEBUG_CURRENT_VERSION 1
@@ -2108,9 +2113,10 @@ ppc_linux_nat_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
watchpoints. */
if (m_dreg_interface.hwdebug_p ())
{
- int region_size;
const struct ppc_debug_info &hwdebug_info = (m_dreg_interface
.hwdebug_info ());
+ int region_size = hwdebug_info.data_bp_alignment;
+ int region_align = region_size;
/* Embedded DAC-based processors, like the PowerPC 440 have ranged
watchpoints and can watch any access within an arbitrary memory
@@ -2122,15 +2128,19 @@ ppc_linux_nat_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
return 2;
/* Check if the processor provides DAWR interface. */
if (hwdebug_info.features & PPC_DEBUG_FEATURE_DATA_BP_DAWR)
- /* DAWR interface allows to watch up to 512 byte wide ranges which
- can't cross a 512 byte boundary. */
- region_size = 512;
- else
- region_size = hwdebug_info.data_bp_alignment;
+ {
+ /* DAWR interface allows to watch up to 512 byte wide ranges. */
+ region_size = 512;
+ /* DAWR interface allows to watch up to 512 byte wide ranges which
+ can't cross a 512 byte bondary on machines that doesn't have a
+ second DAWR (P9 or less). */
+ if (!(hwdebug_info.features & PPC_DEBUG_FEATURE_DATA_BP_ARCH_31))
+ region_align = 512;
+ }
/* Server processors provide one hardware watchpoint and addr+len should
fall in the watchable region provided by the ptrace interface. */
- if (region_size
- && (addr + len > (addr & ~(region_size - 1)) + region_size))
+ if (region_align
+ && (addr + len > (addr & ~(region_align - 1)) + region_size))
return 0;
}
/* addr+len must fall in the 8 byte watchable region for DABR-based