[PATCH v1 1/1] x86/platform/quark: Print boundaries correctly

From: Andy Shevchenko
Date: Wed Jan 20 2016 - 14:20:10 EST


When we print values, such as @size, we have to understand that it's derived
from [begin .. end] as:

size = end - begin + 1

On the opposite the @end is derived from the rest as:

end = begin + size - 1

Correct the IMR code to print values correctly.

Note that @__end_rodata actually points to the next address after the aligned
.rodata section.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
arch/x86/platform/intel-quark/imr.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/platform/intel-quark/imr.c b/arch/x86/platform/intel-quark/imr.c
index 0ee619f..47fd18f 100644
--- a/arch/x86/platform/intel-quark/imr.c
+++ b/arch/x86/platform/intel-quark/imr.c
@@ -228,11 +228,12 @@ static int imr_dbgfs_state_show(struct seq_file *s, void *unused)
if (imr_is_enabled(&imr)) {
base = imr_to_phys(imr.addr_lo);
end = imr_to_phys(imr.addr_hi) + IMR_MASK;
+ size = end - base + 1;
} else {
base = 0;
end = 0;
+ size = 0;
}
- size = end - base;
seq_printf(s, "imr%02i: base=%pa, end=%pa, size=0x%08zx "
"rmask=0x%08x, wmask=0x%08x, %s, %s\n", i,
&base, &end, size, imr.rmask, imr.wmask,
@@ -598,14 +599,17 @@ static void __init imr_fixup_memmap(struct imr_device *idev)
* Setup a locked IMR around the physical extent of the kernel
* from the beginning of the .text secton to the end of the
* .rodata section as one physically contiguous block.
+ *
+ * We don't round up @size since it is already PAGE_SIZE aligned.
+ * See vmlinux.lds.S for details.
*/
ret = imr_add_range(base, size, IMR_CPU, IMR_CPU, true);
if (ret < 0) {
pr_err("unable to setup IMR for kernel: (%p - %p)\n",
- &_text, &__end_rodata);
+ &_text, &__end_rodata - 1);
} else {
pr_info("protecting kernel .text - .rodata: %zu KiB (%p - %p)\n",
- size / 1024, &_text, &__end_rodata);
+ size / 1024, &_text, &__end_rodata - 1);
}

}
--
2.7.0.rc3