libunwind/libunwind-1.6.2-dynamic-page-size.patch
2022-08-28 18:57:54 +02:00

356 lines
9.6 KiB
Diff

From cf6b9aadd60a85107afe5196251ca2ed198a96d0 Mon Sep 17 00:00:00 2001
From: Daniel Moody <daniel.moody@mongodb.com>
Date: Fri, 18 Feb 2022 14:24:37 -0600
Subject: [PATCH] Updated to determine PAGE_SIZE dynamically.
---
include/libunwind_i.h | 9 +++++++++
src/aarch64/Ginit.c | 19 ++++++++-----------
src/arm/Ginit.c | 13 ++-----------
src/mi/init.c | 28 ++++++++++++++++++++++++++--
src/riscv/Ginit.c | 22 ++++++++--------------
src/s390x/Ginit.c | 25 ++++++++++---------------
src/x86/Ginit.c | 13 ++-----------
src/x86_64/Ginit.c | 18 +++++-------------
8 files changed, 70 insertions(+), 77 deletions(-)
diff --git a/include/libunwind_i.h b/include/libunwind_i.h
index 6c7dda9a8..bcf229566 100644
--- a/include/libunwind_i.h
+++ b/include/libunwind_i.h
@@ -55,6 +55,8 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
+#include <errno.h>
+#include <stdio.h>
#if defined(HAVE_ELF_H)
# include <elf.h>
@@ -288,6 +290,13 @@ print_error (const char *string)
return write (2, string, strlen (string));
}
+HIDDEN extern long unw_page_size;
+
+static inline unw_word_t uwn_page_start(unw_word_t addr)
+{
+ return addr & ~(unw_page_size - 1);
+}
+
#define mi_init UNWI_ARCH_OBJ(mi_init)
extern void mi_init (void); /* machine-independent initializations */
diff --git a/src/aarch64/Ginit.c b/src/aarch64/Ginit.c
index 2b08feb36..fe6e511df 100644
--- a/src/aarch64/Ginit.c
+++ b/src/aarch64/Ginit.c
@@ -84,8 +84,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
return 0;
}
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
static int mem_validate_pipe[2] = {-1, -1};
@@ -197,11 +195,14 @@ tdep_init_mem_validate (void)
#ifdef HAVE_MINCORE
unsigned char present = 1;
- unw_word_t addr = PAGE_START((unw_word_t)&present);
+ size_t len = unw_page_size;
+ unw_word_t addr = uwn_page_start((unw_word_t)&present);
unsigned char mvec[1];
int ret;
- while ((ret = mincore ((void*)addr, PAGE_SIZE, (unsigned char *)mvec)) == -1 &&
- errno == EAGAIN) {}
+ while ((ret = mincore((void *)addr, len, (unsigned char *)mvec)) == -1 &&
+ errno == EAGAIN)
+ {
+ }
if (ret == 0)
{
Debug(1, "using mincore to validate memory\n");
@@ -295,12 +296,8 @@ validate_mem (unw_word_t addr)
{
size_t len;
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;
diff --git a/src/arm/Ginit.c b/src/arm/Ginit.c
index 0bac0d72d..bce52dc34 100644
--- a/src/arm/Ginit.c
+++ b/src/arm/Ginit.c
@@ -71,9 +71,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
return 0;
}
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
-
/* Cache of already validated addresses */
#define NLGA 4
static unw_word_t last_good_addr[NLGA];
@@ -83,14 +80,8 @@ static int
validate_mem (unw_word_t addr)
{
int i, victim;
- size_t len;
-
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ size_t len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;
diff --git a/src/mi/init.c b/src/mi/init.c
index 60a48c589..aa9319981 100644
--- a/src/mi/init.c
+++ b/src/mi/init.c
@@ -39,6 +39,30 @@ static const char rcsid[] UNUSED =
long unwi_debug_level;
#endif /* UNW_DEBUG */
+long unw_page_size;
+static void
+unw_init_page_size ()
+{
+ errno = 0;
+ long result = sysconf (_SC_PAGESIZE);
+ if (result == -1)
+ {
+ if (errno != 0)
+ {
+ print_error ("Failed to get _SC_PAGESIZE: ");
+ print_error (strerror(errno));
+ print_error ("\n");
+ }
+ else
+ print_error ("Failed to get _SC_PAGESIZE, errno was not set.\n");
+
+ unw_page_size = 4096;
+ }
+ else
+ {
+ unw_page_size = result;
+ }
+}
HIDDEN void
mi_init (void)
@@ -55,6 +79,6 @@ mi_init (void)
setbuf (stderr, NULL);
}
#endif
-
- assert (sizeof (struct cursor) <= sizeof (unw_cursor_t));
+ unw_init_page_size();
+ assert(sizeof(struct cursor) <= sizeof(unw_cursor_t));
}
diff --git a/src/riscv/Ginit.c b/src/riscv/Ginit.c
index 907f72962..4faeecbfd 100644
--- a/src/riscv/Ginit.c
+++ b/src/riscv/Ginit.c
@@ -97,9 +97,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
// Memory validation routines are from aarch64
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
-
static int mem_validate_pipe[2] = {-1, -1};
#ifdef HAVE_PIPE2
@@ -210,11 +207,14 @@ tdep_init_mem_validate (void)
#ifdef HAVE_MINCORE
unsigned char present = 1;
- unw_word_t addr = PAGE_START((unw_word_t)&present);
+ size_t len = unw_page_size;
+ unw_word_t addr = uwn_page_start((unw_word_t)&present);
unsigned char mvec[1];
int ret;
- while ((ret = mincore ((void*)addr, PAGE_SIZE, (unsigned char *)mvec)) == -1 &&
- errno == EAGAIN) {}
+ while ((ret = mincore((void *)addr, len, (unsigned char *)mvec)) == -1 &&
+ errno == EAGAIN)
+ {
+ }
if (ret == 0)
{
Debug(1, "using mincore to validate memory\n");
@@ -306,14 +306,8 @@ cache_valid_mem(unw_word_t addr)
static int
validate_mem (unw_word_t addr)
{
- size_t len;
-
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ size_t len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;
diff --git a/src/s390x/Ginit.c b/src/s390x/Ginit.c
index db01743c0..2bce2f4b6 100644
--- a/src/s390x/Ginit.c
+++ b/src/s390x/Ginit.c
@@ -27,6 +27,7 @@ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
+#include "libunwind_i.h"
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
@@ -93,9 +94,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
return 0;
}
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
-
static int mem_validate_pipe[2] = {-1, -1};
static inline void
@@ -163,7 +161,7 @@ static int mincore_validate (void *addr, size_t len)
return -1;
}
- for (i = 0; i < (len + PAGE_SIZE - 1) / PAGE_SIZE; i++)
+ for (i = 0; i < (len + unw_page_size - 1) / unw_page_size; i++)
{
if (!(mvec[i] & 1)) return -1;
}
@@ -183,11 +181,14 @@ tdep_init_mem_validate (void)
#ifdef HAVE_MINCORE
unsigned char present = 1;
- unw_word_t addr = PAGE_START((unw_word_t)&present);
+ size_t len = unw_page_size;
+ unw_word_t addr = uwn_page_start((unw_word_t)&present);
unsigned char mvec[1];
int ret;
- while ((ret = mincore ((void*)addr, PAGE_SIZE, mvec)) == -1 &&
- errno == EAGAIN) {}
+ while ((ret = mincore((void *)addr, len, mvec)) == -1 &&
+ errno == EAGAIN)
+ {
+ }
if (ret == 0 && (mvec[0] & 1))
{
Debug(1, "using mincore to validate memory\n");
@@ -210,14 +211,8 @@ static int
validate_mem (unw_word_t addr)
{
int i, victim;
- size_t len;
-
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ size_t len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;
diff --git a/src/x86/Ginit.c b/src/x86/Ginit.c
index 3cec74a21..4261fb523 100644
--- a/src/x86/Ginit.c
+++ b/src/x86/Ginit.c
@@ -74,9 +74,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
return 0;
}
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
-
/* Cache of already validated addresses */
#define NLGA 4
static unw_word_t last_good_addr[NLGA];
@@ -89,14 +86,8 @@ validate_mem (unw_word_t addr)
#ifdef HAVE_MINCORE
unsigned char mvec[2]; /* Unaligned access may cross page boundary */
#endif
- size_t len;
-
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ size_t len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;
diff --git a/src/x86_64/Ginit.c b/src/x86_64/Ginit.c
index 0b121bc91..e75f92a5f 100644
--- a/src/x86_64/Ginit.c
+++ b/src/x86_64/Ginit.c
@@ -73,9 +73,6 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
return 0;
}
-#define PAGE_SIZE 4096
-#define PAGE_START(a) ((a) & ~(PAGE_SIZE-1))
-
static int mem_validate_pipe[2] = {-1, -1};
#ifdef HAVE_PIPE2
@@ -191,10 +188,11 @@ tdep_init_mem_validate (void)
#ifdef HAVE_MINCORE
unsigned char present = 1;
- unw_word_t addr = PAGE_START((unw_word_t)&present);
+ size_t len = unw_page_size;
+ unw_word_t addr = uwn_page_start((unw_word_t)&present);
unsigned char mvec[1];
int ret;
- while ((ret = mincore ((void*)addr, PAGE_SIZE, (unsigned char *)mvec)) == -1 &&
+ while ((ret = mincore ((void*)addr, len, (unsigned char *)mvec)) == -1 &&
errno == EAGAIN) {}
if (ret == 0)
{
@@ -287,14 +285,8 @@ cache_valid_mem(unw_word_t addr)
static int
validate_mem (unw_word_t addr)
{
- size_t len;
-
- if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
- len = PAGE_SIZE;
- else
- len = PAGE_SIZE * 2;
-
- addr = PAGE_START(addr);
+ size_t len = unw_page_size;
+ addr = uwn_page_start(addr);
if (addr == 0)
return -1;