[dpdk-dev] [PATCH v2 2/2] eal: use base address hint to reserve space for mem config
flat view
From: Anatoly Burakov <hidden>
Date: 2019-07-30 15:38:07
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
Currently, mem config will be mapped without using the virtual
area reservation infrastructure, which means it will be mapped
at an arbitrary location. This may cause failures to map the
shared config in secondary process due to things like PCI
whitelist arguments allocating memory in a space where the
primary has allocated the shared mem config.
Fix this by using virtual area reservation to reserve space for
the mem config, thereby avoiding the problem and reserving the
shared config (hopefully) far away from any normal memory
allocations.
Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <redacted>
---
Notes:
v2:
- Fix issue with unneeded ADDR_IS_HINT flag that broke things
on 32-bit builds
lib/librte_eal/freebsd/eal/eal.c | 26 ++++++++++++++++++++------
lib/librte_eal/linux/eal/eal.c | 29 +++++++++++++++++++++--------
2 files changed, 41 insertions(+), 14 deletions(-)
diff --git a/lib/librte_eal/freebsd/eal/eal.c b/lib/librte_eal/freebsd/eal/eal.c
index d53f0fe69..5d2e147b1 100644
--- a/lib/librte_eal/freebsd/eal/eal.c
+++ b/lib/librte_eal/freebsd/eal/eal.c@@ -219,7 +219,8 @@ eal_parse_sysfs_value(const char *filename, unsigned long *val) static int rte_eal_config_create(void) { - void *rte_mem_cfg_addr; + size_t cfg_len = sizeof(*rte_config.mem_config); + void *rte_mem_cfg_addr, *mapped_mem_cfg_addr; int retval; const char *pathname = eal_runtime_config_path();
@@ -236,7 +237,7 @@ rte_eal_config_create(void) } } - retval = ftruncate(mem_cfg_fd, sizeof(*rte_config.mem_config)); + retval = ftruncate(mem_cfg_fd, cfg_len); if (retval < 0){ close(mem_cfg_fd); mem_cfg_fd = -1;
@@ -254,15 +255,28 @@ rte_eal_config_create(void) return -1; } - rte_mem_cfg_addr = mmap(NULL, sizeof(*rte_config.mem_config), - PROT_READ | PROT_WRITE, MAP_SHARED, mem_cfg_fd, 0); - - if (rte_mem_cfg_addr == MAP_FAILED){ + /* reserve space for config */ + rte_mem_cfg_addr = eal_get_virtual_area(NULL, &cfg_len, + sysconf(_SC_PAGESIZE), 0, 0); + if (rte_mem_cfg_addr == NULL) { RTE_LOG(ERR, EAL, "Cannot mmap memory for rte_config\n"); close(mem_cfg_fd); mem_cfg_fd = -1; return -1; } + + /* remap the actual file into the space we've just reserved */ + mapped_mem_cfg_addr = mmap(rte_mem_cfg_addr, + cfg_len, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_FIXED, mem_cfg_fd, 0); + if (mapped_mem_cfg_addr == MAP_FAILED) { + RTE_LOG(ERR, EAL, "Cannot remap memory for rte_config\n"); + munmap(rte_mem_cfg_addr, cfg_len); + close(mem_cfg_fd); + mem_cfg_fd = -1; + return -1; + } + memcpy(rte_mem_cfg_addr, &early_mem_config, sizeof(early_mem_config)); rte_config.mem_config = rte_mem_cfg_addr;
diff --git a/lib/librte_eal/linux/eal/eal.c b/lib/librte_eal/linux/eal/eal.c
index 34db78753..bfd3bc2da 100644
--- a/lib/librte_eal/linux/eal/eal.c
+++ b/lib/librte_eal/linux/eal/eal.c@@ -305,7 +305,8 @@ eal_parse_sysfs_value(const char *filename, unsigned long *val) static int rte_eal_config_create(void) { - void *rte_mem_cfg_addr; + size_t cfg_len = sizeof(*rte_config.mem_config); + void *rte_mem_cfg_addr, *mapped_mem_cfg_addr; int retval; const char *pathname = eal_runtime_config_path();
@@ -330,7 +331,7 @@ rte_eal_config_create(void) } } - retval = ftruncate(mem_cfg_fd, sizeof(*rte_config.mem_config)); + retval = ftruncate(mem_cfg_fd, cfg_len); if (retval < 0){ close(mem_cfg_fd); mem_cfg_fd = -1;
@@ -348,13 +349,25 @@ rte_eal_config_create(void) return -1; } - rte_mem_cfg_addr = mmap(rte_mem_cfg_addr, sizeof(*rte_config.mem_config), - PROT_READ | PROT_WRITE, MAP_SHARED, mem_cfg_fd, 0); - - if (rte_mem_cfg_addr == MAP_FAILED){ - close(mem_cfg_fd); - mem_cfg_fd = -1; + /* reserve space for config */ + rte_mem_cfg_addr = eal_get_virtual_area(rte_mem_cfg_addr, &cfg_len, + sysconf(_SC_PAGESIZE), 0, 0); + if (rte_mem_cfg_addr == NULL) { RTE_LOG(ERR, EAL, "Cannot mmap memory for rte_config\n"); + close(mem_cfg_fd); + mem_cfg_fd = -1; + return -1; + } + + /* remap the actual file into the space we've just reserved */ + mapped_mem_cfg_addr = mmap(rte_mem_cfg_addr, + cfg_len, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_FIXED, mem_cfg_fd, 0); + if (mapped_mem_cfg_addr == MAP_FAILED) { + munmap(rte_mem_cfg_addr, cfg_len); + close(mem_cfg_fd); + mem_cfg_fd = -1; + RTE_LOG(ERR, EAL, "Cannot remap memory for rte_config\n"); return -1; }
--
2.17.1