From ed27521eaee0dd334c658fb68d0c8ebaa6a126cc Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Mon, 1 Jun 2015 23:58:59 -0500 Subject: [PATCH 038/143] cpu/amd/car: Add romstage BSP stack overrun detection Change-Id: Ia2e8f99be9df388e492a633c49df21ca1c57ba13 Signed-off-by: Timothy Pearson --- 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 6542906..4ccde3f 100644 --- a/src/cpu/amd/car/cache_as_ram.inc +++ b/src/cpu/amd/car/cache_as_ram.inc @@ -24,7 +24,7 @@ #include #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 @@ -473,6 +473,10 @@ fam10_end_part1: 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 257b41a..787bedd 100644 --- a/src/cpu/amd/car/post_cache_as_ram.c +++ b/src/cpu/amd/car/post_cache_as_ram.c @@ -110,6 +110,14 @@ 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) -- 1.7.9.5