From 3f649ab728cda8038259d8f14492fe400fbab911 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Jun 2020 13:09:38 -0700 Subject: treewide: Remove uninitialized_var() usage Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe # IB Acked-by: Kalle Valo # wireless drivers Reviewed-by: Chao Yu # erofs Signed-off-by: Kees Cook --- arch/mips/lib/dump_tlb.c | 2 +- arch/mips/mm/init.c | 2 +- arch/mips/mm/tlb-r4k.c | 6 +++--- 3 files changed, 5 insertions(+), 5 deletions(-) (limited to 'arch/mips') diff --git a/arch/mips/lib/dump_tlb.c b/arch/mips/lib/dump_tlb.c index 5a418ba5e75f..4256423632c4 100644 --- a/arch/mips/lib/dump_tlb.c +++ b/arch/mips/lib/dump_tlb.c @@ -79,7 +79,7 @@ static void dump_tlb(int first, int last) unsigned int pagemask, guestctl1 = 0, c0, c1, i; unsigned long asidmask = cpu_asid_mask(¤t_cpu_data); int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4); - unsigned long uninitialized_var(s_mmid); + unsigned long s_mmid; #ifdef CONFIG_32BIT bool xpa = cpu_has_xpa && (read_c0_pagegrain() & PG_ELPA); int pwidth = xpa ? 11 : 8; diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index 336b58173dc7..6c7bbfe35ba3 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -83,7 +83,7 @@ void setup_zero_pages(void) static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot) { enum fixed_addresses idx; - unsigned int uninitialized_var(old_mmid); + unsigned int old_mmid; unsigned long vaddr, flags, entrylo; unsigned long old_ctx; pte_t pte; diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index 6677dcb72580..38e2894d5fa3 100644 --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -119,7 +119,7 @@ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, if (size <= (current_cpu_data.tlbsizeftlbsets ? current_cpu_data.tlbsize / 8 : current_cpu_data.tlbsize / 2)) { - unsigned long old_entryhi, uninitialized_var(old_mmid); + unsigned long old_entryhi, old_mmid; int newpid = cpu_asid(cpu, mm); old_entryhi = read_c0_entryhi(); @@ -213,7 +213,7 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) int cpu = smp_processor_id(); if (cpu_context(cpu, vma->vm_mm) != 0) { - unsigned long uninitialized_var(old_mmid); + unsigned long old_mmid; unsigned long flags, old_entryhi; int idx; @@ -382,7 +382,7 @@ void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1, #ifdef CONFIG_XPA panic("Broken for XPA kernels"); #else - unsigned int uninitialized_var(old_mmid); + unsigned int old_mmid; unsigned long flags; unsigned long wired; unsigned long old_pagemask; -- cgit v1.2.3-59-g8ed1b