ANDROID: arm64: process: dump memory around registers when displaying regs
A port of 8608d7c4418c75841c562a90cddd9beae5798a48 to ARM64. Both the
original code and this port are limited to dumping kernel addresses, so
don't bother if the registers are from a userspace process.
Change-Id: Idc76804c54efaaeb70311cbb500c54db6dac4525
Signed-off-by: Greg Hackmann <ghackmann@google.com>
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 01753cd..2a47416 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -166,6 +166,70 @@
while (1);
}
+/*
+ * dump a block of kernel memory from around the given address
+ */
+static void show_data(unsigned long addr, int nbytes, const char *name)
+{
+ int i, j;
+ int nlines;
+ u32 *p;
+
+ /*
+ * don't attempt to dump non-kernel addresses or
+ * values that are probably just small negative numbers
+ */
+ if (addr < PAGE_OFFSET || addr > -256UL)
+ return;
+
+ printk("\n%s: %#lx:\n", name, addr);
+
+ /*
+ * round address down to a 32 bit boundary
+ * and always dump a multiple of 32 bytes
+ */
+ p = (u32 *)(addr & ~(sizeof(u32) - 1));
+ nbytes += (addr & (sizeof(u32) - 1));
+ nlines = (nbytes + 31) / 32;
+
+
+ for (i = 0; i < nlines; i++) {
+ /*
+ * just display low 16 bits of address to keep
+ * each line of the dump < 80 characters
+ */
+ printk("%04lx ", (unsigned long)p & 0xffff);
+ for (j = 0; j < 8; j++) {
+ u32 data;
+ if (probe_kernel_address(p, data)) {
+ printk(" ********");
+ } else {
+ printk(" %08x", data);
+ }
+ ++p;
+ }
+ printk("\n");
+ }
+}
+
+static void show_extra_register_data(struct pt_regs *regs, int nbytes)
+{
+ mm_segment_t fs;
+ unsigned int i;
+
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+ show_data(regs->pc - nbytes, nbytes * 2, "PC");
+ show_data(regs->regs[30] - nbytes, nbytes * 2, "LR");
+ show_data(regs->sp - nbytes, nbytes * 2, "SP");
+ for (i = 0; i < 30; i++) {
+ char name[4];
+ snprintf(name, sizeof(name), "X%u", i);
+ show_data(regs->regs[i] - nbytes, nbytes * 2, name);
+ }
+ set_fs(fs);
+}
+
void __show_regs(struct pt_regs *regs)
{
int i, top_reg;
@@ -201,6 +265,8 @@
pr_cont("\n");
}
+ if (!user_mode(regs))
+ show_extra_register_data(regs, 128);
printk("\n");
}