From 98bfc9b038cde1ce108f69a50720e394fe774cb7 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 3 Dec 2018 18:03:47 +0100 Subject: [PATCH] x86/mm/cpa: Make cpa_data::vaddr invariant Currently __change_page_attr_set_clr() will modify cpa->vaddr when !(CPA_ARRAY | CPA_PAGES_ARRAY), whereas in the array cases it will increment cpa->curpage. Change __cpa_addr() such that its @idx argument also works in the !array case and use cpa->curpage increments for all cases. NOTE: since cpa_data::numpages is 'unsigned long' so should cpa_data::curpage be. NOTE: after this only cpa->numpages is still modified. Signed-off-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Tom.StDenis@amd.com Cc: dave.hansen@intel.com Link: http://lkml.kernel.org/r/20181203171043.295174892@infradead.org Signed-off-by: Ingo Molnar --- arch/x86/mm/pageattr.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 6e6900ebea30..ce8af3f08628 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -35,11 +35,11 @@ struct cpa_data { pgprot_t mask_set; pgprot_t mask_clr; unsigned long numpages; - int flags; + unsigned long curpage; unsigned long pfn; - unsigned force_split : 1, + unsigned int flags; + unsigned int force_split : 1, force_static_prot : 1; - int curpage; struct page **pages; }; @@ -228,7 +228,7 @@ static bool __cpa_pfn_in_highmap(unsigned long pfn) #endif -static unsigned long __cpa_addr(struct cpa_data *cpa, int idx) +static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx) { if (cpa->flags & CPA_PAGES_ARRAY) { struct page *page = cpa->pages[idx]; @@ -242,7 +242,7 @@ static unsigned long __cpa_addr(struct cpa_data *cpa, int idx) if (cpa->flags & CPA_ARRAY) return cpa->vaddr[idx]; - return *cpa->vaddr; + return *cpa->vaddr + idx * PAGE_SIZE; } /* @@ -1581,6 +1581,7 @@ static int cpa_process_alias(struct cpa_data *cpa) alias_cpa = *cpa; alias_cpa.vaddr = &laddr; alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); + alias_cpa.curpage = 0; ret = __change_page_attr_set_clr(&alias_cpa, 0); if (ret) @@ -1600,6 +1601,7 @@ static int cpa_process_alias(struct cpa_data *cpa) alias_cpa = *cpa; alias_cpa.vaddr = &temp_cpa_vaddr; alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); + alias_cpa.curpage = 0; /* * The high mapping range is imprecise, so ignore the @@ -1648,11 +1650,7 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) */ BUG_ON(cpa->numpages > numpages || !cpa->numpages); numpages -= cpa->numpages; - if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) - cpa->curpage++; - else - *cpa->vaddr += cpa->numpages * PAGE_SIZE; - + cpa->curpage += cpa->numpages; } return 0; } -- GitLab