diff options
Diffstat (limited to 'sys-kernel/cairn-sources/files/5.10.10/hardened-patches/0107-mm-Fix-extra_latent_entropy.patch')
| -rw-r--r-- | sys-kernel/cairn-sources/files/5.10.10/hardened-patches/0107-mm-Fix-extra_latent_entropy.patch | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/sys-kernel/cairn-sources/files/5.10.10/hardened-patches/0107-mm-Fix-extra_latent_entropy.patch b/sys-kernel/cairn-sources/files/5.10.10/hardened-patches/0107-mm-Fix-extra_latent_entropy.patch new file mode 100644 index 000000000000..d60949d64658 --- /dev/null +++ b/sys-kernel/cairn-sources/files/5.10.10/hardened-patches/0107-mm-Fix-extra_latent_entropy.patch @@ -0,0 +1,103 @@ +From 3f29827dd2c6423c43d0e8e73c2e13685c7e7a4b Mon Sep 17 00:00:00 2001 +From: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr> +Date: Tue, 7 May 2019 11:46:21 +0200 +Subject: [PATCH 107/113] mm: Fix extra_latent_entropy + +Commit a9cd410a3d29 ("mm/page_alloc.c: memory hotplug: free pages as +higher order") changed `static void __init __free_pages_boot_core()` +into `void __free_pages_core()`, causing the following section mismatch +warning at compile time: + + WARNING: vmlinux.o(.text+0x180fe4): Section mismatch in reference from the function __free_pages_core() to the variable .meminit.data:extra_latent_entropy + The function __free_pages_core() references the variable __meminitdata extra_latent_entropy. + This is often because __free_pages_core lacks a __meminitdata annotation or the annotation of extra_latent_entropy is wrong. + +This commit is an attempt at fixing this issue. I'm not sure it's OK as +we are accessing pages that are still managed by the bootmem allocator. +The prefetching part is not an issue as it only affects struct pages. + +Signed-off-by: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr> +--- + mm/page_alloc.c | 38 ++++++++++++++++++++++---------------- + 1 file changed, 22 insertions(+), 16 deletions(-) + +diff --git a/mm/page_alloc.c b/mm/page_alloc.c +index ded9e8536285..8730ae4244b9 100644 +--- a/mm/page_alloc.c ++++ b/mm/page_alloc.c +@@ -1539,6 +1539,25 @@ static void __free_pages_ok(struct page *page, unsigned int order, + local_irq_restore(flags); + } + ++static void __init __gather_extra_latent_entropy(struct page *page, ++ unsigned int nr_pages) ++{ ++ if (extra_latent_entropy && !PageHighMem(page) && page_to_pfn(page) < 0x100000) { ++ unsigned long hash = 0; ++ size_t index, end = PAGE_SIZE * nr_pages / sizeof hash; ++ const unsigned long *data = lowmem_page_address(page); ++ ++ for (index = 0; index < end; index++) ++ hash ^= hash + data[index]; ++#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY ++ latent_entropy ^= hash; ++ add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy)); ++#else ++ add_device_randomness((const void *)&hash, sizeof(hash)); ++#endif ++ } ++} ++ + void __free_pages_core(struct page *page, unsigned int order) + { + unsigned int nr_pages = 1 << order; +@@ -1558,22 +1577,6 @@ void __free_pages_core(struct page *page, unsigned int order) + } + __ClearPageReserved(p); + set_page_count(p, 0); +- +- if (extra_latent_entropy && !PageHighMem(page) && page_to_pfn(page) < 0x100000) { +- unsigned long hash = 0; +- size_t index, end = PAGE_SIZE * nr_pages / sizeof hash; +- const unsigned long *data = lowmem_page_address(page); +- +- for (index = 0; index < end; index++) +- hash ^= hash + data[index]; +-#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY +- latent_entropy ^= hash; +- add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy)); +-#else +- add_device_randomness((const void *)&hash, sizeof(hash)); +-#endif +- } +- + atomic_long_add(nr_pages, &page_zone(page)->managed_pages); + + /* +@@ -1632,6 +1635,7 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, + { + if (early_page_uninitialised(pfn)) + return; ++ __gather_extra_latent_entropy(page, 1 << order); + __free_pages_core(page, order); + } + +@@ -1723,6 +1727,7 @@ static void __init deferred_free_range(unsigned long pfn, + if (nr_pages == pageblock_nr_pages && + (pfn & (pageblock_nr_pages - 1)) == 0) { + set_pageblock_migratetype(page, MIGRATE_MOVABLE); ++ __gather_extra_latent_entropy(page, 1 << pageblock_order); + __free_pages_core(page, pageblock_order); + return; + } +@@ -1730,6 +1735,7 @@ static void __init deferred_free_range(unsigned long pfn, + for (i = 0; i < nr_pages; i++, page++, pfn++) { + if ((pfn & (pageblock_nr_pages - 1)) == 0) + set_pageblock_migratetype(page, MIGRATE_MOVABLE); ++ __gather_extra_latent_entropy(page, 1); + __free_pages_core(page, 0); + } + } +-- +2.30.0 + |