From 5a0e3ad6af8660be21ca98a971cd00f331318c05 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 24 Mar 2010 17:04:11 +0900 Subject: include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn --- virt/kvm/assigned-dev.c | 1 + virt/kvm/coalesced_mmio.c | 1 + virt/kvm/eventfd.c | 1 + virt/kvm/ioapic.c | 1 + virt/kvm/irq_comm.c | 1 + virt/kvm/kvm_main.c | 2 +- 6 files changed, 6 insertions(+), 1 deletion(-) (limited to 'virt') diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c index 057e2cca6af..02ff2b19dbe 100644 --- a/virt/kvm/assigned-dev.c +++ b/virt/kvm/assigned-dev.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "irq.h" static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *head, diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c index 5169736377a..36e25802964 100644 --- a/virt/kvm/coalesced_mmio.c +++ b/virt/kvm/coalesced_mmio.c @@ -10,6 +10,7 @@ #include "iodev.h" #include +#include #include #include "coalesced_mmio.h" diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 7016319b1ec..b81f0ebbaaa 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "iodev.h" diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c index 3db15a807f8..03a5eb22da2 100644 --- a/virt/kvm/ioapic.c +++ b/virt/kvm/ioapic.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index 9fd5b3ebc51..a0e88809e45 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -20,6 +20,7 @@ */ #include +#include #include #include diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 548f9253c19..5a0cd194dce 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -22,7 +22,6 @@ #include #include #include -#include #include #include #include @@ -46,6 +45,7 @@ #include #include #include +#include #include #include -- cgit v1.2.3 From 87bf6e7de1134f48681fd2ce4b7c1ec45458cb6d Mon Sep 17 00:00:00 2001 From: Takuya Yoshikawa Date: Mon, 12 Apr 2010 19:35:35 +0900 Subject: KVM: fix the handling of dirty bitmaps to avoid overflows Int is not long enough to store the size of a dirty bitmap. This patch fixes this problem with the introduction of a wrapper function to calculate the sizes of dirty bitmaps. Note: in mark_page_dirty(), we have to consider the fact that __set_bit() takes the offset as int, not long. Signed-off-by: Takuya Yoshikawa Signed-off-by: Marcelo Tosatti --- virt/kvm/kvm_main.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5a0cd194dce..364daacafb5 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -648,7 +648,7 @@ skip_lpage: /* Allocate page dirty bitmap if needed */ if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) { - unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8; + unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(&new); new.dirty_bitmap = vmalloc(dirty_bytes); if (!new.dirty_bitmap) @@ -768,7 +768,7 @@ int kvm_get_dirty_log(struct kvm *kvm, { struct kvm_memory_slot *memslot; int r, i; - int n; + unsigned long n; unsigned long any = 0; r = -EINVAL; @@ -780,7 +780,7 @@ int kvm_get_dirty_log(struct kvm *kvm, if (!memslot->dirty_bitmap) goto out; - n = ALIGN(memslot->npages, BITS_PER_LONG) / 8; + n = kvm_dirty_bitmap_bytes(memslot); for (i = 0; !any && i < n/sizeof(long); ++i) any = memslot->dirty_bitmap[i]; @@ -1186,10 +1186,13 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn) memslot = gfn_to_memslot_unaliased(kvm, gfn); if (memslot && memslot->dirty_bitmap) { unsigned long rel_gfn = gfn - memslot->base_gfn; + unsigned long *p = memslot->dirty_bitmap + + rel_gfn / BITS_PER_LONG; + int offset = rel_gfn % BITS_PER_LONG; /* avoid RMW */ - if (!generic_test_le_bit(rel_gfn, memslot->dirty_bitmap)) - generic___set_le_bit(rel_gfn, memslot->dirty_bitmap); + if (!generic_test_le_bit(offset, p)) + generic___set_le_bit(offset, p); } } -- cgit v1.2.3 From eda2beda835697878e309b6049aa0a3bad051590 Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Tue, 20 Apr 2010 14:29:29 +0800 Subject: KVM: Add missing srcu_read_lock() for kvm_mmu_notifier_release() I got this dmesg due to srcu_read_lock() is missing in kvm_mmu_notifier_release(). =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- arch/x86/kvm/x86.h:72 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 2 locks held by qemu-system-x86/3100: #0: (rcu_read_lock){.+.+..}, at: [] __mmu_notifier_release+0x38/0xdf #1: (&(&kvm->mmu_lock)->rlock){+.+...}, at: [] kvm_mmu_zap_all+0x21/0x5e [kvm] stack backtrace: Pid: 3100, comm: qemu-system-x86 Not tainted 2.6.34-rc3-22949-gbc8a97a-dirty #2 Call Trace: [] lockdep_rcu_dereference+0xaa/0xb3 [] unalias_gfn+0x56/0xab [kvm] [] gfn_to_memslot+0x16/0x25 [kvm] [] gfn_to_rmap+0x17/0x6e [kvm] [] rmap_remove+0xa0/0x19d [kvm] [] kvm_mmu_zap_page+0x109/0x34d [kvm] [] kvm_mmu_zap_all+0x35/0x5e [kvm] [] kvm_arch_flush_shadow+0x16/0x22 [kvm] [] kvm_mmu_notifier_release+0x15/0x17 [kvm] [] __mmu_notifier_release+0x88/0xdf [] ? __mmu_notifier_release+0x38/0xdf [] ? exit_mm+0xe0/0x115 [] exit_mmap+0x2c/0x17e [] mmput+0x2d/0xd4 [] exit_mm+0x108/0x115 [...] Signed-off-by: Lai Jiangshan Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 364daacafb5..c82ae249263 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -341,7 +341,11 @@ static void kvm_mmu_notifier_release(struct mmu_notifier *mn, struct mm_struct *mm) { struct kvm *kvm = mmu_notifier_to_kvm(mn); + int idx; + + idx = srcu_read_lock(&kvm->srcu); kvm_arch_flush_shadow(kvm); + srcu_read_unlock(&kvm->srcu, idx); } static const struct mmu_notifier_ops kvm_mmu_notifier_ops = { -- cgit v1.2.3