[Skiboot] [PATCH] hdata: Ignore unnamed memory reservations.

[Oliver O'Halloran]

On Fri, May 26, 2017 at 4:39 PM, Gavin Shan <gwshan at linux.vnet.ibm.com> wrote:
> On Fri, May 26, 2017 at 04:18:29PM +1000, Oliver O'Halloran wrote:
>>Hostboot should name any and all memory reservations that it provides.
>>Currently some hostboots export a broken reservation covering the first
>>256MB of memory and this causes the system to crash at boot due to an
>>invalid free because this overlaps with the static "ibm,os-reserve"
>>region (which covers the first 768MB of memory).
>>
>>According to the hostboot team unnamed reservations are invalid and can
>>be ignored.
>>
>>Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
>
> Reviewed-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
> Tested-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
>
>>---
>> hdata/memory.c | 6 +++---
>> 1 file changed, 3 insertions(+), 3 deletions(-)
>>
>>diff --git a/hdata/memory.c b/hdata/memory.c
>>index 0c6c0811f61a..26c8a9837b73 100644
>>--- a/hdata/memory.c
>>+++ b/hdata/memory.c
>>@@ -409,7 +409,7 @@ static void get_hb_reserved_mem(struct HDIF_common_hdr *ms_vpd)
>> {
>>       const struct msvpd_hb_reserved_mem *hb_resv_mem;
>>       u64 start_addr, end_addr, label_size;
>>-      int unnamed = 0, count, i;
>>+      int count, i;
>>       char *label;
>>
>>       /*
>>@@ -463,9 +463,9 @@ static void get_hb_reserved_mem(struct HDIF_common_hdr *ms_vpd)
>>               memcpy(label, hb_resv_mem->label, label_size);
>>               label[label_size] = '\0';
>>
>>+              /* Unnamed reservations are always broken. Ignore them. */
>>               if (strlen(label) == 0)
>>-                      snprintf(label, 64, "hostboot-reserve-%d", unnamed++);
>>-
>>+                      continue;
>
> When the memory block allocated and tracked by @label isn't used, it needs to be
> free'd? However, I believe not too much memory wasted though :)

Ah yeah, true. That used to be stack-allocated.

>
>>
>>               prlog(PR_DEBUG, "MEM: Reserve '%s' %#" PRIx64 "-%#" PRIx64 " (type/inst=0x%08x)\n",
>>                     label, start_addr, end_addr, be32_to_cpu(hb_resv_mem->type_instance));
>
> Cheers,
> Gavin
>