Timothy Pearson (tpearson@raptorengineeringinc.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/11970
-gerrit
commit 8145913b72f5d5cdc85fbba0ce2ba13dd3e9374a Author: Timothy Pearson tpearson@raptorengineeringinc.com Date: Mon Jun 1 23:58:59 2015 -0500
cpu/amd/car: Add romstage BSP stack overrun detection
Change-Id: Ia2e8f99be9df388e492a633c49df21ca1c57ba13 Signed-off-by: Timothy Pearson tpearson@raptorengineeringinc.com --- src/cpu/amd/car/cache_as_ram.inc | 6 +++++- src/cpu/amd/car/post_cache_as_ram.c | 8 ++++++++ 2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/src/cpu/amd/car/cache_as_ram.inc b/src/cpu/amd/car/cache_as_ram.inc index 9874ec4..3295ccc 100644 --- a/src/cpu/amd/car/cache_as_ram.inc +++ b/src/cpu/amd/car/cache_as_ram.inc @@ -20,7 +20,7 @@ #include <cpu/amd/mtrr.h>
#define CacheSize CONFIG_DCACHE_RAM_SIZE -#define CacheBase (0xd0000 - CacheSize) +#define CacheBase CONFIG_DCACHE_RAM_BASE #define CacheSizeBSPStack CONFIG_DCACHE_BSP_STACK_SIZE #define CacheSizeBSPSlush CONFIG_DCACHE_BSP_STACK_SLUSH
@@ -496,6 +496,10 @@ CAR_skip_k8_errata_part2: movl $(CacheBase + CacheSize), %eax movl %eax, %esp
+ /* Poison the lower stack boundary */ + movl $((CacheBase + CacheSize) - CacheSizeBSPStack), %eax + movl $0xdeadbeef, (%eax) + post_code(0xa3)
jmp CAR_FAM10_ap_out diff --git a/src/cpu/amd/car/post_cache_as_ram.c b/src/cpu/amd/car/post_cache_as_ram.c index 49b9ee3..0865b42 100644 --- a/src/cpu/amd/car/post_cache_as_ram.c +++ b/src/cpu/amd/car/post_cache_as_ram.c @@ -98,6 +98,14 @@ void post_cache_as_ram(void) void *resume_backup_memory = NULL; uint32_t family = amd_fam1x_cpu_family();
+ /* Verify that the BSP didn't overrun the lower stack + * boundary during romstage execution + */ + volatile uint32_t *lower_stack_boundary; + lower_stack_boundary = (void *)((CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE) - CONFIG_STACK_SIZE); + if ((*lower_stack_boundary) != 0xdeadbeef) + printk(BIOS_WARNING, "BSP overran lower stack boundary. Undefined behaviour may result!\n"); + struct romstage_handoff *handoff; handoff = romstage_handoff_find_or_add(); if (handoff != NULL)