gdb/SOURCES/gdb-rhbz1854784-powerpc-remove-region-limit-dawr-7of7.patch
2021-12-07 18:11:52 +00:00

74 lines
2.9 KiB
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From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Rogerio Alves <rcardoso@linux.ibm.com>
Date: Wed, 7 Jul 2021 19:06:52 -0400
Subject: gdb-rhbz1854784-powerpc-remove-region-limit-dawr-7of7.patch
;; Backport "PowerPC remove 512 bytes region limit if 2nd DAWR is available."
;; (Rogerio Alves, RH BZ 1854784)
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
@@ -144,6 +144,11 @@ 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
@@ -2121,9 +2126,10 @@ 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
@@ -2135,15 +2141,19 @@ 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