The alignment constraint is defined in the CSM specifications as "Bit mapped. First non-zero bit from the right is the alignment."
Use __fls() to sanitise the alignment given that definition, since passing a non-power-of-two alignment to _malloc() isn't going to work well. And cope with being passed zero, which was happening for the E820 table allocation from EDK2.
Signed-off-by: David Woodhouse dwmw2@infradead.org --- src/fw/csm.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/src/fw/csm.c b/src/fw/csm.c index 03b4bb8..bf7b8f5 100644 --- a/src/fw/csm.c +++ b/src/fw/csm.c @@ -264,6 +264,13 @@ handle_csm_0006(struct bregs *regs) dprintf(3, "Legacy16GetTableAddress size %x align %x region %d\n", size, align, region);
+ // DX = Required address alignment. Bit mapped. + // First non-zero bit from the right is the alignment.*/ + if (align) + align = 1 << __ffs(align); + else + align = 1; + if (region & 2) chunk = _malloc(&ZoneLow, size, align); if (!chunk && (region & 1))