On Fri, Sep 12, 2008 at 02:50:33PM -0500, Anthony Liguori wrote:
> Eduardo Habkost wrote:
>> On some cases, such as under KVM, tb_invalidate_phys_page_range()
>> may be called for large addresses, when qemu is configured to more than
>> 4GB of RAM.
>>
>> On these cases, qemu was crashing because it was using an index too
>> large for l1_map[], that supports only 32-bit addresses when compiling
>> without CONFIG_USER_ONLY.
>>
>
> Did you have kqemu enabled in the build? l1_map should be sufficiently
> large when you have kqemu disabled.
KVM uses './configure --disable-kqemu', but exec.c has this:
#if defined(CONFIG_USER_ONLY) && defined(TARGET_VIRT_ADDR_SPACE_BITS)
/* XXX: this is a temporary hack for alpha target.
* In the future, this is to be replaced by a multi-level table
* to actually be able to handle the complete 64 bits address space.
*/
#define L1_BITS (TARGET_VIRT_ADDR_SPACE_BITS - L2_BITS - TARGET_PAGE_BITS)
#else
#define L1_BITS (32 - L2_BITS - TARGET_PAGE_BITS)
#endif
And CONFIG_USER_ONLY is not defined, making l1_map work only for 32-bit
addresses.
BTW, I've just noticed page_find_alloc() has this:
#if TARGET_LONG_BITS > 32
/* Host memory outside guest VM. For 32-bit targets we have already
excluded high addresses. */
if (index > ((target_ulong)L2_SIZE * L1_SIZE))
return NULL;
#endif
So, we can just use a similar check on page_find().
Side note: the check on the kvm git tree looks broken: it is checking
for (L2_SIZE * L1_SIZE * TARGET_PAGE_SIZE) instead.
--
Eduardo
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
