[coreboot-gerrit] Patch set updated for coreboot: 7e1f8e4 vboot2: Reduce minimum required work buffer size

[Patrick Georgi (pgeorgi@google.com)]

Patrick Georgi (pgeorgi at google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9445

-gerrit

commit 7e1f8e43ffa4ce51e90a2c64bd737e28a1f4113a
Author: Julius Werner <jwerner at chromium.org>
Date:   Mon Dec 1 13:11:52 2014 -0800

    vboot2: Reduce minimum required work buffer size
    
    Apparently our initial submission of 16K was a little too generous for
    the vboot2 work buffer, and I hear that we should also be well within
    bounds for 12K. This patch reduces the minimum asserted by memlayout so
    some of our low-mem boards can get a few more kilobytes back for
    discretionary spending. Also changes the required minimum alignment to 8
    since that's what the current vboot code aligns it to anyway, and add a
    warning comment to make it clearer that this is a dangerous number
    people should not be playing with lightly.
    
    BRANCH=None
    BUG=None
    TEST=Built and booted on Pinky.
    
    Original-Change-Id: Iae9c74050500a315c90f5d5517427d755ac1dfea
    Original-Signed-off-by: Julius Werner <jwerner at chromium.org>
    Original-Reviewed-on: https://chromium-review.googlesource.com/232613
    Original-Reviewed-by: Randall Spangler <rspangler at chromium.org>
    Original-Reviewed-by: Aaron Durbin <adurbin at chromium.org>
    
    (cherry picked from commit 64e972f10363451cd544fdf8642bd484463703bc)
    Signed-off-by: Aaron Durbin <adurbin at chromium.org>
    
    Change-Id: I362b8c33cf79534bb76bd7acda44d467563fe133
---
 src/vendorcode/google/chromeos/vboot2/memlayout.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/vendorcode/google/chromeos/vboot2/memlayout.h b/src/vendorcode/google/chromeos/vboot2/memlayout.h
index 9e19200..7903dd2 100644
--- a/src/vendorcode/google/chromeos/vboot2/memlayout.h
+++ b/src/vendorcode/google/chromeos/vboot2/memlayout.h
@@ -22,9 +22,12 @@
 #ifndef __CHROMEOS_VBOOT2_MEMLAYOUT_H
 #define __CHROMEOS_VBOOT2_MEMLAYOUT_H
 
+/* Careful: required work buffer size depends on RW properties such as key size
+ * and algorithm -- what works for you might stop working after an update. Do
+ * NOT lower the asserted minimum without consulting vboot devs (rspangler)! */
 #define VBOOT2_WORK(addr, size) \
-	REGION(vboot2_work, addr, size, 4) \
-	_ = ASSERT(size >= 16K, "vboot2 work buffer must be at least 16K!");
+	REGION(vboot2_work, addr, size, 8) \
+	_ = ASSERT(size >= 12K, "vboot2 work buffer must be at least 12K!");
 
 #ifdef __VERSTAGE__
 	#define VERSTAGE(addr, sz) \