motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-03 15:53:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

cpu-exec: fix lock hierarchy for user-mode emulation

Browse source 
tb_lock has to be taken inside the mmap_lock (example:
tb_invalidate_phys_range is called by target_mmap), but
tb_link_page is taking the mmap_lock and it is called
with the tb_lock held.

To fix this, take the mmap_lock in tb_find_slow, not
in tb_link_page.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2015-08-11 11:33:24 +02:00
parent 8fd19e6cfd
commit 9fd1a94888
2 changed files with 55 additions and 22 deletions
Download patch file Download diff file Expand all files Collapse all files

6
translate-all.c
View file

@ -1375,6 +1375,8 @@ static inline void tb_alloc_page(TranslationBlock *tb,
/* add a new TB and link it to the physical page tables. phys_page2 is
* (-1) to indicate that only one page contains the TB.
*
* Called with mmap_lock held for user-mode emulation.
*/
static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
tb_page_addr_t phys_page2)
@ -1382,9 +1384,6 @@ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
unsigned int h;
TranslationBlock **ptb;
/* Grab the mmap lock to stop another thread invalidating this TB
before we are done. */
mmap_lock();
/* add in the physical hash table */
h = tb_phys_hash_func(phys_pc);
ptb = &tcg_ctx.tb_ctx.tb_phys_hash[h];
@ -1414,7 +1413,6 @@ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
#ifdef DEBUG_TB_CHECK
tb_page_check();
#endif
mmap_unlock();
}
/* find the TB 'tb' such that tb[0].tc_ptr <= tc_ptr <