diff options
Diffstat (limited to '0003-efi-efi_memmap_insert-don-t-insert-a-region-more-tha.patch')
| -rw-r--r-- | 0003-efi-efi_memmap_insert-don-t-insert-a-region-more-tha.patch | 114 |
1 files changed, 0 insertions, 114 deletions
diff --git a/0003-efi-efi_memmap_insert-don-t-insert-a-region-more-tha.patch b/0003-efi-efi_memmap_insert-don-t-insert-a-region-more-tha.patch deleted file mode 100644 index aceeb1d0c..000000000 --- a/0003-efi-efi_memmap_insert-don-t-insert-a-region-more-tha.patch +++ /dev/null @@ -1,114 +0,0 @@ -From f6e5aedc786ca2360a9b2aaa2fc31769a9c182d0 Mon Sep 17 00:00:00 2001 -From: Peter Jones <pjones@redhat.com> -Date: Wed, 7 Dec 2016 14:41:25 -0500 -Subject: [PATCH 3/4] efi: efi_memmap_insert(): don't insert a region more than - once - -Some machines, such as the Lenovo ThinkPad W541 with firmware GNET80WW -(2.28), include memory map entries with phys_addr=0x0 and num_pages=0. - -When this is true on a machine with an ESRT config table, -efi_esrt_init() will try to reserve that table with efi_mem_reserve(). -When it does, efi_arch_mem_reserve() will use efi_mem_desc_lookup() to -find the memory map in question, call efi_memmap_split_count() to -determine how many regions it will be split into, allocates new ram for -the map, and calls efi_memmap_insert() to add the entry. - -efi_memmap_insert() iterates across all regions in the old map, and for -each region, it tests whether the address for the new map is within that -region. Unfortunately we'll try to insert the new map in *each* of -these entries, causing even more duplicate entries. But -efi_memmap_split_count() only returned the split count for the first -entry, because it was called with the result of efi_mem_desc_lookup(), -which only returns the first entry it came across. As a result, this -will overflow the memory map's allocation and eventually panic. - -Unfortunately the method of computing the size does not handle the -0xffffffffffffffff or 0x0 edge cases well, and all valid addresses wind -up being covered by any such entry. Even if the math weren't off by 1 -byte in the num_pages=0 case, a duplicate entry in the table, or an -entry with num_pages of ((u64)-1LL >> EFI_PAGE_SHIFT) or (u64)-1LL (i.e. -either the maximum number of virtually addressable pages or just the -largest value you can stuff in the field) would have the same effect. - -In any case, if we see more than one memory map in efi_memmap_insert() -that covers the same region, it is an error to try to split up more than -one of them, overflowing the allocation. So this makes it never try to -split more than one region per invocation of efi_arch_mem_reserve(). - -I have not attempted to address the math error. - -Signed-off-by: Peter Jones <pjones@redhat.com> ---- - drivers/firmware/efi/memmap.c | 29 ++++++++++++++++++++++++++++- - 1 file changed, 28 insertions(+), 1 deletion(-) - -diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c -index f03ddec..5b71c717 100644 ---- a/drivers/firmware/efi/memmap.c -+++ b/drivers/firmware/efi/memmap.c -@@ -219,6 +219,7 @@ void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf, - efi_memory_desc_t *md; - u64 start, end; - void *old, *new; -+ bool did_split=false; - - /* modifying range */ - m_start = mem->range.start; -@@ -251,6 +252,15 @@ void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf, - - if (m_start <= start && - (start < m_end && m_end < end)) { -+ if (did_split) { -+ pr_warn_once("%s: memory map for 0x%llx pages at 0x%016llx also covers address 0x%016llx. Not splitting.\n", -+ __func__, -+ md->num_pages, md->phys_addr, -+ m_start); -+ continue; -+ } -+ -+ did_split = true; - /* first part */ - md->attribute |= m_attr; - md->num_pages = (m_end - md->phys_addr + 1) >> -@@ -265,9 +275,18 @@ void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf, - } - - if ((start < m_start && m_start < end) && m_end < end) { -+ if (did_split) { -+ pr_warn_once("%s: memory map for 0x%llx pages at 0x%016llx also covers address 0x%016llx. Not splitting.\n", -+ __func__, -+ md->num_pages, md->phys_addr, -+ m_start); -+ continue; -+ } -+ did_split = true; - /* first part */ - md->num_pages = (m_start - md->phys_addr) >> - EFI_PAGE_SHIFT; -+ - /* middle part */ - new += old_memmap->desc_size; - memcpy(new, old, old_memmap->desc_size); -@@ -284,9 +303,17 @@ void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf, - md->num_pages = (end - m_end) >> - EFI_PAGE_SHIFT; - } -- -+// else - if ((start < m_start && m_start < end) && - (end <= m_end)) { -+ if (did_split) { -+ pr_warn_once("%s: memory map for 0x%llx pages at 0x%016llx also covers address 0x%016llx. Not splitting.\n", -+ __func__, -+ md->num_pages, md->phys_addr, -+ m_start); -+ continue; -+ } -+ did_split = true; - /* first part */ - md->num_pages = (m_start - md->phys_addr) >> - EFI_PAGE_SHIFT; --- -2.9.3 - |